diff --git a/alembic/env.py b/alembic/env.py
index dbaa994..33b893e 100644
--- a/alembic/env.py
+++ b/alembic/env.py
@@ -49,6 +49,7 @@ from app.modules.notice_cases import models as notice_cases_models  # noqa: F401
 from app.modules.registrations import models as registration_models  # noqa: F401
 from app.modules.credential_vault import models as credential_vault_models  # noqa: F401
 from app.modules.client_identity import models as client_identity_models  # noqa: F401
+from app.modules.accounting import accounting_mirror_models as accounting_mirror_models  # noqa: F401
 
 config = context.config
 
diff --git a/alembic/versions/20260918_accounting_mirror_registry.py b/alembic/versions/20260918_accounting_mirror_registry.py
new file mode 100644
index 0000000..554014f
--- /dev/null
+++ b/alembic/versions/20260918_accounting_mirror_registry.py
@@ -0,0 +1,52 @@
+"""Accounting Mirror client/FY registry.
+
+Revision ID: 20260918_accounting_mirror_reg
+Revises: 20260903_tds_withholding_tools
+"""
+from alembic import op
+import sqlalchemy as sa
+
+revision = "20260918_accounting_mirror_reg"
+down_revision = "20260903_tds_withholding_tools"
+branch_labels = None
+depends_on = None
+
+
+def upgrade() -> None:
+    op.create_table(
+        "accounting_mirror_registry",
+        sa.Column("id", sa.Integer(), primary_key=True, autoincrement=True),
+        sa.Column("tenant_id", sa.Integer(), sa.ForeignKey("tenants.id", ondelete="CASCADE"), nullable=False),
+        sa.Column("client_id", sa.Integer(), sa.ForeignKey("clients.id", ondelete="CASCADE"), nullable=False),
+        sa.Column("storage_node_id", sa.Integer(), sa.ForeignKey("branch_storage_nodes.id", ondelete="SET NULL"), nullable=True),
+        sa.Column("financial_year", sa.String(length=7), nullable=False),
+        sa.Column("accounting_relative_dir", sa.String(length=1000), nullable=False),
+        sa.Column("mirror_file_name", sa.String(length=255), nullable=False),
+        sa.Column("company_name", sa.String(length=255), nullable=False, server_default=""),
+        sa.Column("company_guid", sa.String(length=160), nullable=False, server_default=""),
+        sa.Column("voucher_from_date", sa.Date(), nullable=True),
+        sa.Column("voucher_to_date", sa.Date(), nullable=True),
+        sa.Column("file_size_bytes", sa.BigInteger(), nullable=False, server_default="0"),
+        sa.Column("status", sa.String(length=30), nullable=False, server_default="active"),
+        sa.Column("is_active", sa.Boolean(), nullable=False, server_default=sa.true()),
+        sa.Column("replacement_count", sa.Integer(), nullable=False, server_default="0"),
+        sa.Column("created_by_user_id", sa.Integer(), sa.ForeignKey("users.id", ondelete="SET NULL"), nullable=True),
+        sa.Column("last_synced_by_user_id", sa.Integer(), sa.ForeignKey("users.id", ondelete="SET NULL"), nullable=True),
+        sa.Column("created_at_utc", sa.DateTime(timezone=True), nullable=False),
+        sa.Column("last_synced_at_utc", sa.DateTime(timezone=True), nullable=True),
+        sa.Column("updated_at_utc", sa.DateTime(timezone=True), nullable=False),
+        sa.UniqueConstraint("tenant_id", "client_id", "financial_year", name="uq_accounting_mirror_registry_client_fy"),
+    )
+    for name, col in (
+        ("ix_accounting_mirror_registry_tenant_id", "tenant_id"),
+        ("ix_accounting_mirror_registry_client_id", "client_id"),
+        ("ix_accounting_mirror_registry_storage_node_id", "storage_node_id"),
+        ("ix_accounting_mirror_registry_financial_year", "financial_year"),
+        ("ix_accounting_mirror_registry_status", "status"),
+        ("ix_accounting_mirror_registry_is_active", "is_active"),
+    ):
+        op.create_index(name, "accounting_mirror_registry", [col], unique=False)
+
+
+def downgrade() -> None:
+    op.drop_table("accounting_mirror_registry")
diff --git a/app/modules/accounting/accounting_mirror_models.py b/app/modules/accounting/accounting_mirror_models.py
new file mode 100644
index 0000000..14cd01c
--- /dev/null
+++ b/app/modules/accounting/accounting_mirror_models.py
@@ -0,0 +1,51 @@
+from __future__ import annotations
+
+from datetime import date, datetime, timezone
+
+from sqlalchemy import BigInteger, Boolean, Date, DateTime, ForeignKey, Integer, String, UniqueConstraint
+from sqlalchemy.orm import Mapped, mapped_column
+
+from app.core.db.common import CommonBase
+
+
+def _utcnow() -> datetime:
+    return datetime.now(timezone.utc)
+
+
+class AccountingMirrorRegistry(CommonBase):
+    """Authoritative link between one ERP client/FY and its active local .act mirror."""
+
+    __tablename__ = "accounting_mirror_registry"
+    __table_args__ = (
+        UniqueConstraint(
+            "tenant_id",
+            "client_id",
+            "financial_year",
+            name="uq_accounting_mirror_registry_client_fy",
+        ),
+    )
+
+    id: Mapped[int] = mapped_column(Integer, primary_key=True, autoincrement=True)
+    tenant_id: Mapped[int] = mapped_column(ForeignKey("tenants.id", ondelete="CASCADE"), nullable=False, index=True)
+    client_id: Mapped[int] = mapped_column(ForeignKey("clients.id", ondelete="CASCADE"), nullable=False, index=True)
+    storage_node_id: Mapped[int | None] = mapped_column(ForeignKey("branch_storage_nodes.id", ondelete="SET NULL"), nullable=True, index=True)
+
+    financial_year: Mapped[str] = mapped_column(String(7), nullable=False, index=True)
+    accounting_relative_dir: Mapped[str] = mapped_column(String(1000), nullable=False)
+    mirror_file_name: Mapped[str] = mapped_column(String(255), nullable=False)
+
+    company_name: Mapped[str] = mapped_column(String(255), nullable=False, default="")
+    company_guid: Mapped[str] = mapped_column(String(160), nullable=False, default="")
+    voucher_from_date: Mapped[date | None] = mapped_column(Date, nullable=True)
+    voucher_to_date: Mapped[date | None] = mapped_column(Date, nullable=True)
+    file_size_bytes: Mapped[int] = mapped_column(BigInteger, nullable=False, default=0)
+
+    status: Mapped[str] = mapped_column(String(30), nullable=False, default="active", index=True)
+    is_active: Mapped[bool] = mapped_column(Boolean, nullable=False, default=True, index=True)
+    replacement_count: Mapped[int] = mapped_column(Integer, nullable=False, default=0)
+
+    created_by_user_id: Mapped[int | None] = mapped_column(ForeignKey("users.id", ondelete="SET NULL"), nullable=True)
+    last_synced_by_user_id: Mapped[int | None] = mapped_column(ForeignKey("users.id", ondelete="SET NULL"), nullable=True)
+    created_at_utc: Mapped[datetime] = mapped_column(DateTime(timezone=True), nullable=False, default=_utcnow)
+    last_synced_at_utc: Mapped[datetime | None] = mapped_column(DateTime(timezone=True), nullable=True)
+    updated_at_utc: Mapped[datetime] = mapped_column(DateTime(timezone=True), nullable=False, default=_utcnow, onupdate=_utcnow)
diff --git a/app/modules/accounting/accounting_mirror_registry.py b/app/modules/accounting/accounting_mirror_registry.py
new file mode 100644
index 0000000..b389a3b
--- /dev/null
+++ b/app/modules/accounting/accounting_mirror_registry.py
@@ -0,0 +1,181 @@
+from __future__ import annotations
+
+from datetime import date, datetime, timezone
+from pathlib import Path
+import re
+from typing import Any
+
+from sqlalchemy import select
+
+from app.modules.accounting.accounting_mirror_models import AccountingMirrorRegistry
+
+
+def _utcnow() -> datetime:
+    return datetime.now(timezone.utc)
+
+
+def _fy_key(value: str) -> int:
+    match = re.fullmatch(r"(\d{4})-(\d{2})", str(value or "").strip())
+    return int(match.group(1)) if match else -1
+
+
+def _get_any_mirror(db, tenant_id: int, client_id: int, financial_year: str) -> AccountingMirrorRegistry | None:
+    return db.execute(
+        select(AccountingMirrorRegistry).where(
+            AccountingMirrorRegistry.tenant_id == int(tenant_id),
+            AccountingMirrorRegistry.client_id == int(client_id),
+            AccountingMirrorRegistry.financial_year == str(financial_year or "").strip(),
+        )
+    ).scalar_one_or_none()
+
+
+def get_registered_mirror(db, tenant_id: int, client_id: int, financial_year: str) -> AccountingMirrorRegistry | None:
+    row = _get_any_mirror(db, tenant_id, client_id, financial_year)
+    return row if row and row.is_active and row.status == "active" else None
+
+
+def list_registered_mirrors(db, tenant_id: int, client_id: int) -> list[AccountingMirrorRegistry]:
+    rows = db.execute(
+        select(AccountingMirrorRegistry).where(
+            AccountingMirrorRegistry.tenant_id == int(tenant_id),
+            AccountingMirrorRegistry.client_id == int(client_id),
+            AccountingMirrorRegistry.is_active.is_(True),
+        )
+    ).scalars().all()
+    return sorted(rows, key=lambda row: _fy_key(row.financial_year), reverse=True)
+
+
+def _parse_iso_date(value: Any) -> date | None:
+    text = str(value or "").strip()
+    if not text:
+        return None
+    try:
+        return date.fromisoformat(text[:10])
+    except Exception:
+        return None
+
+
+def _parse_iso_datetime(value: Any) -> datetime | None:
+    text = str(value or "").strip()
+    if not text:
+        return None
+    try:
+        parsed = datetime.fromisoformat(text.replace("Z", "+00:00"))
+        return parsed if parsed.tzinfo else parsed.replace(tzinfo=timezone.utc)
+    except Exception:
+        return None
+
+
+def upsert_registered_mirror(
+    db,
+    *,
+    tenant_id: int,
+    client_id: int,
+    financial_year: str,
+    accounting_relative_dir: str,
+    storage_node_id: int | None,
+    mirror: dict[str, Any] | None = None,
+    job: dict[str, Any] | None = None,
+    requested_by_user_id: int | None = None,
+    replacement: bool = False,
+) -> AccountingMirrorRegistry:
+    mirror = dict(mirror or {})
+    job = dict(job or {})
+    company = dict(mirror.get("company") or {})
+    voucher_period = dict(mirror.get("voucher_period") or {})
+
+    row = _get_any_mirror(db, tenant_id, client_id, financial_year)
+    created = row is None
+    if row is None:
+        row = AccountingMirrorRegistry(
+            tenant_id=int(tenant_id),
+            client_id=int(client_id),
+            financial_year=str(financial_year).strip(),
+            accounting_relative_dir=str(accounting_relative_dir or "").strip(),
+            mirror_file_name=f"client_{int(client_id):08d}.act",
+            created_by_user_id=requested_by_user_id,
+        )
+        db.add(row)
+
+    row.storage_node_id = int(storage_node_id) if storage_node_id else None
+    row.accounting_relative_dir = str(accounting_relative_dir or row.accounting_relative_dir or "").strip()
+    row.mirror_file_name = Path(str(job.get("accounting_db_path") or row.mirror_file_name or f"client_{int(client_id):08d}.act")).name
+    row.company_name = str(
+        job.get("company_name")
+        or company.get("company_name")
+        or row.company_name
+        or ""
+    ).strip()
+    row.company_guid = str(
+        job.get("tally_guid")
+        or company.get("company_guid")
+        or row.company_guid
+        or ""
+    ).strip()
+    row.voucher_from_date = _parse_iso_date(voucher_period.get("from_date")) or row.voucher_from_date
+    row.voucher_to_date = _parse_iso_date(voucher_period.get("to_date")) or row.voucher_to_date
+    try:
+        row.file_size_bytes = int(mirror.get("size_bytes") or row.file_size_bytes or 0)
+    except Exception:
+        pass
+    row.status = "active"
+    row.is_active = True
+    row.last_synced_by_user_id = requested_by_user_id
+    row.last_synced_at_utc = (
+        _parse_iso_datetime(job.get("finished_at_utc"))
+        or _parse_iso_datetime(job.get("updated_at_utc"))
+        or _utcnow()
+    )
+    if replacement and not created:
+        row.replacement_count = int(row.replacement_count or 0) + 1
+    row.updated_at_utc = _utcnow()
+    db.flush()
+    return row
+
+
+def sync_discovered_mirrors(
+    db,
+    *,
+    tenant_id: int,
+    client_id: int,
+    storage_node_id: int | None,
+    discovered: list[dict[str, Any]],
+    requested_by_user_id: int | None = None,
+) -> list[AccountingMirrorRegistry]:
+    output: list[AccountingMirrorRegistry] = []
+    discovered_fys: set[str] = set()
+    for item in discovered or []:
+        fy = str(item.get("financial_year") or "").strip()
+        relative_dir = str(item.get("accounting_relative_dir") or "").strip()
+        mirror = dict(item.get("mirror") or {})
+        if not re.fullmatch(r"\d{4}-\d{2}", fy) or not relative_dir or not mirror.get("ready"):
+            continue
+        discovered_fys.add(fy)
+        row = upsert_registered_mirror(
+            db,
+            tenant_id=tenant_id,
+            client_id=client_id,
+            financial_year=fy,
+            accounting_relative_dir=relative_dir,
+            storage_node_id=storage_node_id,
+            mirror=mirror,
+            job=item,
+            requested_by_user_id=requested_by_user_id,
+            replacement=False,
+        )
+        output.append(row)
+
+    existing = db.execute(
+        select(AccountingMirrorRegistry).where(
+            AccountingMirrorRegistry.tenant_id == int(tenant_id),
+            AccountingMirrorRegistry.client_id == int(client_id),
+            AccountingMirrorRegistry.is_active.is_(True),
+        )
+    ).scalars().all()
+    for row in existing:
+        if row.financial_year not in discovered_fys:
+            row.status = "missing"
+            row.is_active = False
+            row.updated_at_utc = _utcnow()
+    db.commit()
+    return output
diff --git a/app/modules/accounting/creditors_aging_ui.py b/app/modules/accounting/creditors_aging_ui.py
index b1f6866..115d60d 100644
--- a/app/modules/accounting/creditors_aging_ui.py
+++ b/app/modules/accounting/creditors_aging_ui.py
@@ -13,6 +13,12 @@ from app.core.db.common import CommonSessionLocal
 from app.core.security.csrf import get_or_create_csrf_token
 from app.core.templating import templates
 from app.modules.accounting.accounting_mirror_service import AccountingMirrorError, sundry_creditors_aging
+from app.modules.accounting.accounting_mirror_registry import (
+    get_registered_mirror,
+    list_registered_mirrors,
+    sync_discovered_mirrors,
+)
+from app.modules.accounting.agent_bridge import request_agent_command
 from app.modules.accounting.ui import (
     _accounting_storage_payload,
     _active_financial_year,
@@ -43,6 +49,42 @@ def _resolve_fy(value: str, fallback: str) -> str:
     return fallback
 
 
+def _sync_client_mirror_registry(db, node, scope, user, client) -> None:
+    if not node or not _node_online(node) or not client:
+        return
+    try:
+        response = request_agent_command(
+            node.node_code,
+            "accounting_mirror_list",
+            {"client_id": int(client.id)},
+            timeout_seconds=20,
+        )
+        if response.get("ok"):
+            sync_discovered_mirrors(
+                db,
+                tenant_id=scope.tenant_id,
+                client_id=int(client.id),
+                storage_node_id=int(node.id),
+                discovered=(response.get("result") or {}).get("mirrors") or [],
+                requested_by_user_id=int(user.id),
+            )
+    except Exception:
+        pass
+
+
+def _registered_follow_up_fys(db, tenant_id: int, client_id: int, selected_fy: str) -> list[str]:
+    base_start, _ = _financial_year_bounds(selected_fy)
+    values = []
+    for row in list_registered_mirrors(db, tenant_id, client_id):
+        try:
+            start, _ = _financial_year_bounds(row.financial_year)
+        except Exception:
+            continue
+        if start > base_start:
+            values.append(row.financial_year)
+    return sorted(set(values), key=lambda fy: _financial_year_bounds(fy)[0])
+
+
 def _load_analysis(request: Request, db, user, client_id: int, financial_year: str, follow_up_fy: str):
     client, clients, scope = _find_visible_client(db, request, user, client_id)
     if not client:
@@ -51,6 +93,11 @@ def _load_analysis(request: Request, db, user, client_id: int, financial_year: s
     if not node or not _node_online(node):
         return None, clients, scope, "ERP Local Agent is offline for the active branch."
 
+    _sync_client_mirror_registry(db, node, scope, user, client)
+    base_registration = get_registered_mirror(db, scope.tenant_id, int(client.id), financial_year)
+    if not base_registration:
+        return None, clients, scope, f"No registered Accounting Mirror is available for FY {financial_year}. Create the mirror from Tally Accounting first."
+
     fy_start, fy_end = _financial_year_bounds(financial_year)
     follow_up_start = ""
     follow_up_end = ""
@@ -59,6 +106,9 @@ def _load_analysis(request: Request, db, user, client_id: int, financial_year: s
         follow_start, follow_end = _financial_year_bounds(follow_up_fy)
         if follow_start <= fy_end:
             return None, clients, scope, "Follow-up financial year must be after the analysis financial year."
+        follow_up_registration = get_registered_mirror(db, scope.tenant_id, int(client.id), follow_up_fy)
+        if not follow_up_registration:
+            return None, clients, scope, f"No registered Accounting Mirror is available for follow-up FY {follow_up_fy}."
         follow_up_start = follow_start.isoformat()
         follow_up_end = follow_end.isoformat()
         follow_up_payload = _accounting_storage_payload(client, follow_up_fy)
@@ -103,6 +153,13 @@ def creditors_aging(
             selected_fy = fallback_fy
         selected_follow_up = str(follow_up_fy or "").strip()
         selected_client = next((c for c in clients if client_id and int(c.id) == int(client_id)), None)
+        registered_fys: list[str] = []
+        follow_up_options: list[str] = []
+        if selected_client:
+            node = get_active_storage_node_for_branch(db, scope.tenant_id, scope.branch_id)
+            _sync_client_mirror_registry(db, node, scope, user, selected_client)
+            registered_fys = [row.financial_year for row in list_registered_mirrors(db, scope.tenant_id, int(selected_client.id))]
+            follow_up_options = _registered_follow_up_fys(db, scope.tenant_id, int(selected_client.id), selected_fy)
         result = None
         error = ""
         if analyze and selected_client:
@@ -119,7 +176,8 @@ def creditors_aging(
             "selected_client": selected_client,
             "selected_fy": selected_fy,
             "follow_up_fy": selected_follow_up,
-            "fy_options": _fy_options(selected_fy),
+            "fy_options": registered_fys or _fy_options(selected_fy),
+            "follow_up_options": follow_up_options,
             "analysis": result,
             "error": error,
         }
diff --git a/app/modules/accounting/templates/accounting/sundry_creditors_aging.html b/app/modules/accounting/templates/accounting/sundry_creditors_aging.html
index 82549a9..aee9a77 100644
--- a/app/modules/accounting/templates/accounting/sundry_creditors_aging.html
+++ b/app/modules/accounting/templates/accounting/sundry_creditors_aging.html
@@ -21,14 +21,14 @@
       </select>
     </label>
     <label class="space-y-1 text-sm"><span class="font-semibold text-slate-700">Analysis FY</span>
-      <select name="financial_year" data-creditor-analysis-fy class="w-full rounded-xl border border-slate-300 px-3 py-2">
+      <select id="creditorAnalysisFY" name="financial_year" class="w-full rounded-xl border border-slate-300 px-3 py-2">
         {% for fy in fy_options %}<option value="{{ fy }}" {% if fy == selected_fy %}selected{% endif %}>{{ fy }}</option>{% endfor %}
       </select>
     </label>
     <label class="space-y-1 text-sm"><span class="font-semibold text-slate-700">Follow-up FY (optional)</span>
-      <select name="follow_up_fy" data-creditor-follow-up-fy class="w-full rounded-xl border border-slate-300 px-3 py-2">
+      <select id="creditorFollowUpFY" name="follow_up_fy" class="w-full rounded-xl border border-slate-300 px-3 py-2">
         <option value="">Do not trace later payments</option>
-        {% for fy in fy_options %}{% if fy > selected_fy %}<option value="{{ fy }}" {% if fy == follow_up_fy %}selected{% endif %}>{{ fy }}</option>{% endif %}{% endfor %}
+        {% for fy in follow_up_options %}<option value="{{ fy }}" {% if fy == follow_up_fy %}selected{% endif %}>{{ fy }}</option>{% endfor %}
       </select>
     </label>
     <div class="flex items-end"><button class="w-full rounded-xl bg-brand-600 px-4 py-2 text-sm font-semibold text-white hover:bg-brand-700">Analyse Creditors</button></div>
@@ -141,69 +141,30 @@
   {% endif %}
 </div>
 
+<script>
+(function(){
+  const analysis=document.getElementById('creditorAnalysisFY');
+  const follow=document.getElementById('creditorFollowUpFY');
+  const registered={{ (fy_options or [])|tojson }};
+  if(!analysis||!follow)return;
+  function startYear(fy){const m=/^(\d{4})-\d{2}$/.exec(fy||'');return m?parseInt(m[1],10):-1;}
+  function rebuild(){
+    const chosen=follow.value;
+    const base=startYear(analysis.value);
+    follow.innerHTML='';
+    const empty=document.createElement('option'); empty.value=''; empty.textContent='Do not trace later payments'; follow.appendChild(empty);
+    registered.slice().sort((a,b)=>startYear(a)-startYear(b)).forEach(function(fy){
+      if(startYear(fy)<=base)return;
+      const opt=document.createElement('option'); opt.value=fy; opt.textContent=fy; if(fy===chosen)opt.selected=true; follow.appendChild(opt);
+    });
+  }
+  analysis.addEventListener('change',rebuild);
+  rebuild();
+})();
+</script>
+
 <script>
 (function () {
-  // Keep Follow-up FY synchronized with the Analysis FY on the client side.
-  // Previously the server rendered follow-up options only for the FY that was
-  // active when the page loaded. If the user changed Analysis FY in the form
-  // (for example 2026-27 -> 2021-22), the Follow-up FY control still showed
-  // 2027-28 until the page was submitted. Rebuild it immediately from the FY
-  // values already supplied by the server, without changing any accounting or
-  // FIFO calculation logic.
-  var analysisFySelect = document.querySelector('[data-creditor-analysis-fy]');
-  var followUpFySelect = document.querySelector('[data-creditor-follow-up-fy]');
-
-  function fyStartYear(value) {
-    var match = String(value || '').match(/^(\d{4})-\d{2}$/);
-    return match ? parseInt(match[1], 10) : null;
-  }
-
-  if (analysisFySelect && followUpFySelect) {
-    var fyUniverse = Array.from(analysisFySelect.options)
-      .map(function (option) { return String(option.value || '').trim(); })
-      .filter(function (value) { return fyStartYear(value) !== null; });
-
-    function rebuildFollowUpYears() {
-      var selectedFy = String(analysisFySelect.value || '').trim();
-      var selectedStart = fyStartYear(selectedFy);
-      var previousFollowUp = String(followUpFySelect.value || '').trim();
-
-      while (followUpFySelect.options.length) {
-        followUpFySelect.remove(0);
-      }
-
-      var emptyOption = document.createElement('option');
-      emptyOption.value = '';
-      emptyOption.textContent = 'Do not trace later payments';
-      followUpFySelect.appendChild(emptyOption);
-
-      if (selectedStart === null) return;
-
-      var laterYears = fyUniverse
-        .filter(function (fy) {
-          var start = fyStartYear(fy);
-          return start !== null && start > selectedStart;
-        })
-        .sort(function (a, b) { return fyStartYear(a) - fyStartYear(b); });
-
-      laterYears.forEach(function (fy) {
-        var option = document.createElement('option');
-        option.value = fy;
-        option.textContent = fy;
-        followUpFySelect.appendChild(option);
-      });
-
-      if (laterYears.indexOf(previousFollowUp) !== -1) {
-        followUpFySelect.value = previousFollowUp;
-      } else {
-        followUpFySelect.value = '';
-      }
-    }
-
-    analysisFySelect.addEventListener('change', rebuildFollowUpYears);
-    rebuildFollowUpYears();
-  }
-
   function applyBucket(detailRow, bucket) {
     if (!detailRow) return;
     detailRow.querySelectorAll('[data-creditor-lot]').forEach(function (lot) {
diff --git a/app/modules/accounting/templates/accounting/tally.html b/app/modules/accounting/templates/accounting/tally.html
index 8a73391..bd8e11d 100644
--- a/app/modules/accounting/templates/accounting/tally.html
+++ b/app/modules/accounting/templates/accounting/tally.html
@@ -290,9 +290,17 @@
       <span class="rounded-full bg-emerald-50 px-3 py-1 text-xs font-semibold text-emerald-700">Read-only export</span>
     </div>
     <div class="mt-4 rounded-xl border border-amber-200 bg-amber-50 px-4 py-3 text-sm text-amber-900"><strong>Before export:</strong> open the mapped company in TallyPrime and set Tally's active period (Alt+F2) to cover the full period you want exported. The ODBC mirror reads Tally's active period; the ERP does not change Tally's period automatically.</div>
+    <div id="mirrorRegistryStatus" class="mt-3 rounded-xl border border-slate-200 bg-slate-50 px-4 py-3 text-sm text-slate-700">
+      {% if selected_mirror_registration %}
+      <strong>Mirror registered:</strong> FY {{ selected_mirror_registration.financial_year }}{% if selected_mirror_registration.company_name %} · {{ selected_mirror_registration.company_name }}{% endif %}{% if selected_mirror_registration.last_synced_at_utc %} · last synced {{ selected_mirror_registration.last_synced_at_utc.strftime('%d-%m-%Y %H:%M') }}{% endif %}. Creating this FY again will ask for replacement confirmation.
+      {% else %}
+      <strong>No registered mirror for FY {{ selected_financial_year }}.</strong> Creating the mirror will register it to this client and financial year for Accounting/Audit tools.
+      {% endif %}
+    </div>
     <form method="post" action="/tools/tally/full-export" class="mt-5 grid gap-4 lg:grid-cols-5 lg:items-end" id="mirrorExportForm">
       <input type="hidden" name="csrf_token" value="{{ csrf_token }}" />
       <input type="hidden" name="client_id" value="{{ selected_client.id }}" />
+      <input type="hidden" name="replace_existing" id="mirrorReplaceExisting" value="" />
       <label class="text-sm font-medium text-slate-700">Target Financial Year
         <select id="mirrorFinancialYear" name="financial_year" required class="mt-1 w-full rounded-xl border border-slate-300 bg-white px-3 py-2 text-sm">
           {% for fy in mirror_fy_options %}
@@ -553,7 +561,7 @@
   function setText(id,v){const e=document.getElementById(id);if(e)e.textContent=String(v??'');}
   async function pollFullExport(){
     try{
-      const r=await fetch('/tools/tally/full-export/status?client_id='+encodeURIComponent(clientId),{cache:'no-store'});
+      const fyEl=document.getElementById('mirrorFinancialYear'); const fyValue=fyEl?fyEl.value:''; const r=await fetch('/tools/tally/full-export/status?client_id='+encodeURIComponent(clientId)+'&financial_year='+encodeURIComponent(fyValue),{cache:'no-store'});
       const d=await r.json(); if(!r.ok||!d.ok||!d.job)return;
       const j=d.job||{}, p=Math.max(0,Math.min(100,Number(j.percent)||0)); box.classList.remove('hidden');
       setText('fullExportStage',j.stage||j.status||'Working…'); setText('fullExportMessage',j.message||''); setText('fullExportPct',Math.round(p)+'%');
@@ -609,6 +617,49 @@ document.addEventListener("DOMContentLoaded", function () {
       applyFY(fy.value);
     }
   });
+
+  const mirrorForm=document.getElementById("mirrorExportForm");
+  const replaceField=document.getElementById("mirrorReplaceExisting");
+  const registryStatus=document.getElementById("mirrorRegistryStatus");
+  let confirmingMirror=false;
+  async function refreshMirrorRegistrationStatus(){
+    if(!fy||!clientId)return;
+    try{
+      const r=await fetch('/tools/tally/mirror-registration/status?client_id='+encodeURIComponent(clientId)+'&financial_year='+encodeURIComponent(fy.value),{cache:'no-store'});
+      const d=await r.json();
+      if(!r.ok||!d.ok)return;
+      if(registryStatus){
+        registryStatus.innerHTML=d.exists
+          ? '<strong>Mirror registered:</strong> FY '+fy.value+(d.company_name?' · '+d.company_name:'')+(d.last_synced_at?' · last synced '+new Date(d.last_synced_at).toLocaleString():'')+'. Creating this FY again will ask for replacement confirmation.'
+          : '<strong>No registered mirror for FY '+fy.value+'.</strong> Creating the mirror will register it to this client and financial year for Accounting/Audit tools.';
+      }
+    }catch(e){}
+  }
+  if(fy)fy.addEventListener("change",refreshMirrorRegistrationStatus);
+  refreshMirrorRegistrationStatus();
+
+  if(mirrorForm){
+    mirrorForm.addEventListener("submit",async function(event){
+      if(confirmingMirror || (replaceField&&replaceField.value==='1'))return;
+      event.preventDefault();
+      try{
+        const r=await fetch('/tools/tally/mirror-registration/status?client_id='+encodeURIComponent(clientId)+'&financial_year='+encodeURIComponent(fy.value),{cache:'no-store'});
+        const d=await r.json();
+        if(!r.ok||!d.ok){ mirrorForm.submit(); return; }
+        if(d.exists){
+          const label=(d.client_name||'this client')+' - FY '+fy.value;
+          const ok=window.confirm('An Accounting Mirror already exists for '+label+'.\n\nReplace the existing mirror?\n\nThe current mirror will remain active if the new export fails.');
+          if(!ok)return;
+          if(replaceField)replaceField.value='1';
+        }
+        confirmingMirror=true;
+        mirrorForm.submit();
+      }catch(e){
+        confirmingMirror=true;
+        mirrorForm.submit();
+      }
+    });
+  }
 });
 </script>
 
diff --git a/app/modules/accounting/ui.py b/app/modules/accounting/ui.py
index fce016b..7087abd 100644
--- a/app/modules/accounting/ui.py
+++ b/app/modules/accounting/ui.py
@@ -22,6 +22,12 @@ from app.modules.core.rbac.deps import get_user_permissions, get_user_roles
 from app.modules.core.rbac.permission_guard import require_permission
 from app.modules.documents.services import build_document_scope, get_active_storage_node_for_branch, client_folder_parts, sanitize_segment
 from app.modules.accounting.agent_bridge import request_agent_command
+from app.modules.accounting.accounting_mirror_registry import (
+    get_registered_mirror,
+    list_registered_mirrors,
+    sync_discovered_mirrors,
+    upsert_registered_mirror,
+)
 from app.modules.registrations.models import ClientRegistration, RegistrationType
 
 
@@ -247,6 +253,30 @@ def tally_tool(
         node = get_active_storage_node_for_branch(db, scope.tenant_id, scope.branch_id)
         online = _node_online(node)
 
+        # Synchronise the cloud-side Client + FY registry from mirrors already
+        # present on the branch Storage Node. This is read-only and also backfills
+        # mirrors created before the registry feature was introduced.
+        if selected_client and node and online:
+            try:
+                discovered_response = request_agent_command(
+                    node.node_code,
+                    "accounting_mirror_list",
+                    {"client_id": int(selected_client.id)},
+                    timeout_seconds=20,
+                )
+                if discovered_response.get("ok"):
+                    sync_discovered_mirrors(
+                        db,
+                        tenant_id=scope.tenant_id,
+                        client_id=int(selected_client.id),
+                        storage_node_id=int(node.id),
+                        discovered=(discovered_response.get("result") or {}).get("mirrors") or [],
+                        requested_by_user_id=int(user.id),
+                    )
+            except Exception:
+                # Mirror discovery must never block the existing Tally page.
+                pass
+
         live_result = None
         analysis_history = []
         command_error = error or ""
@@ -304,6 +334,15 @@ def tally_tool(
             else selected_fy_end.isoformat()
         )
 
+        registered_mirrors = (
+            list_registered_mirrors(db, scope.tenant_id, int(selected_client.id))
+            if selected_client else []
+        )
+        selected_mirror_registration = (
+            get_registered_mirror(db, scope.tenant_id, int(selected_client.id), selected_financial_year)
+            if selected_client else None
+        )
+
         return _render(
             request,
             db,
@@ -325,6 +364,8 @@ def tally_tool(
             selected_financial_year=selected_financial_year,
             workspace_financial_year=workspace_financial_year,
             mirror_fy_options=mirror_fy_options,
+            registered_mirrors=registered_mirrors,
+            selected_mirror_registration=selected_mirror_registration,
             command_error=command_error,
             analysis_history=analysis_history,
         )
@@ -764,6 +805,55 @@ def sync_tally_transactions(
     finally:
         db.close()
 
+
+
+@router.get("/mirror-registration/status")
+def mirror_registration_status(request: Request, client_id: int, financial_year: str):
+    db = CommonSessionLocal()
+    try:
+        user, response = _require_partner(request, db, "accounting.tally.view")
+        if response:
+            return JSONResponse({"ok": False, "error": "Access denied."}, status_code=403)
+        client, _clients, scope = _find_visible_client(db, request, user, client_id)
+        if not client:
+            return JSONResponse({"ok": False, "error": "Client is not available."}, status_code=404)
+        try:
+            _financial_year_bounds(financial_year)
+        except Exception:
+            return JSONResponse({"ok": False, "error": "Invalid financial year."}, status_code=400)
+
+        row = get_registered_mirror(db, scope.tenant_id, int(client.id), financial_year)
+        node = get_active_storage_node_for_branch(db, scope.tenant_id, scope.branch_id)
+        file_exists = False
+        mirror = {}
+        if node and _node_online(node):
+            try:
+                storage_payload = _accounting_storage_payload(client, financial_year)
+                status = request_agent_command(node.node_code, "accounting_mirror_status", storage_payload, timeout_seconds=20)
+                if status.get("ok"):
+                    mirror = (status.get("result") or {}).get("mirror") or {}
+                    file_exists = bool(mirror.get("ready"))
+                    if file_exists:
+                        row = upsert_registered_mirror(
+                            db, tenant_id=scope.tenant_id, client_id=int(client.id), financial_year=financial_year,
+                            accounting_relative_dir=storage_payload["accounting_relative_dir"], storage_node_id=int(node.id),
+                            mirror=mirror, requested_by_user_id=int(user.id), replacement=False,
+                        )
+                        db.commit()
+            except Exception:
+                pass
+        exists = bool(row or file_exists)
+        return JSONResponse({
+            "ok": True,
+            "exists": exists,
+            "financial_year": financial_year,
+            "client_name": client.client_name,
+            "company_name": (row.company_name if row else str((mirror.get("company") or {}).get("company_name") or "")),
+            "last_synced_at": (row.last_synced_at_utc.isoformat() if row and row.last_synced_at_utc else ""),
+        })
+    finally:
+        db.close()
+
 @router.post("/full-export")
 def start_full_accounting_export(
     request: Request,
@@ -772,6 +862,7 @@ def start_full_accounting_export(
     date_from: str = Form(...),
     date_to: str = Form(...),
     financial_year: str = Form(""),
+    replace_existing: str = Form(""),
     csrf_token: str = Form(...),
 ):
     validate_csrf(request, csrf_token)
@@ -800,13 +891,45 @@ def start_full_accounting_export(
         node = get_active_storage_node_for_branch(db, scope.tenant_id, scope.branch_id)
         if not node or not _node_online(node):
             return RedirectResponse(url=f"/tools/tally?client_id={client.id}&error={quote('ERP Local Agent is offline for the active branch.')}", status_code=303)
+
+        storage_payload = _accounting_storage_payload(client, target_fy)
+        existing_registration = get_registered_mirror(db, scope.tenant_id, int(client.id), target_fy)
+        existing_file = False
+        try:
+            current_status = request_agent_command(
+                node.node_code, "accounting_mirror_status", storage_payload, timeout_seconds=20
+            )
+            current_mirror = ((current_status.get("result") or {}).get("mirror") or {}) if current_status.get("ok") else {}
+            existing_file = bool(current_mirror.get("ready"))
+            if existing_file:
+                upsert_registered_mirror(
+                    db, tenant_id=scope.tenant_id, client_id=int(client.id), financial_year=target_fy,
+                    accounting_relative_dir=storage_payload["accounting_relative_dir"], storage_node_id=int(node.id),
+                    mirror=current_mirror, requested_by_user_id=int(user.id), replacement=False,
+                )
+                db.commit()
+        except Exception:
+            existing_file = bool(existing_registration)
+
+        replace_confirmed = str(replace_existing or "").strip().lower() in {"1", "true", "yes", "on"}
+        if (existing_registration or existing_file) and not replace_confirmed:
+            message = (
+                f"An Accounting Mirror already exists for {client.client_name} - FY {target_fy}. "
+                "Use Replace Existing Mirror to refresh it; the current mirror will remain active if the new export fails."
+            )
+            return RedirectResponse(
+                url=f"/tools/tally?client_id={client.id}&financial_year={quote(target_fy)}&error={quote(message)}",
+                status_code=303,
+            )
+
         result = request_agent_command(
             node.node_code, "accounting_full_export_start",
             {
-                **_accounting_storage_payload(client, target_fy),
+                **storage_payload,
                 "tally_guid": str(tally_guid or "").strip(),
                 "date_from": start.isoformat(), "date_to": end.isoformat(),
                 "requested_by_user_id": int(user.id), "timeout_seconds": 1800,
+                "replacement_requested": bool(existing_registration or existing_file),
             }, timeout_seconds=20,
         )
         if not result.get("ok"):
@@ -819,7 +942,7 @@ def start_full_accounting_export(
 
 
 @router.get("/full-export/status")
-def full_accounting_export_status(request: Request, client_id: int):
+def full_accounting_export_status(request: Request, client_id: int, financial_year: str = ""):
     db = CommonSessionLocal()
     try:
         user, response = _require_partner(request, db, "accounting.tally.view")
@@ -837,7 +960,23 @@ def full_accounting_export_status(request: Request, client_id: int):
         )
         if not result.get("ok"):
             return JSONResponse({"ok": False, "error": str(result.get("error") or "Progress lookup failed.")}, status_code=500)
-        return JSONResponse({"ok": True, **(result.get("result") or {})})
+        result_payload = result.get("result") or {}
+        job = result_payload.get("job") or {}
+        if str(job.get("status") or "").lower() == "completed":
+            fy = str(job.get("financial_year") or financial_year or "").strip()
+            if re.fullmatch(r"\d{4}-\d{2}", fy):
+                storage_payload = _accounting_storage_payload(client, fy)
+                try:
+                    upsert_registered_mirror(
+                        db, tenant_id=scope.tenant_id, client_id=int(client.id), financial_year=fy,
+                        accounting_relative_dir=storage_payload["accounting_relative_dir"], storage_node_id=int(node.id),
+                        mirror=job.get("mirror") or {}, job=job, requested_by_user_id=int(user.id),
+                        replacement=bool(job.get("replacement_requested")),
+                    )
+                    db.commit()
+                except Exception:
+                    db.rollback()
+        return JSONResponse({"ok": True, **result_payload})
     finally:
         db.close()
 
diff --git a/app/modules/documents/agent_package.py b/app/modules/documents/agent_package.py
index 6a7b6de..45c3de3 100644
--- a/app/modules/documents/agent_package.py
+++ b/app/modules/documents/agent_package.py
@@ -4,7 +4,7 @@ import io
 from pathlib import Path
 import zipfile
 
-ERP_LOCAL_AGENT_VERSION = "1.26.16"
+ERP_LOCAL_AGENT_VERSION = "1.26.17"
 ERP_LOCAL_AGENT_NAME = "ERP Local Agent"
 RUNTIME_ROOT = Path(__file__).resolve().parent / "local_agent_runtime"
 _DETERMINISTIC_ZIP_TIMESTAMP = (2026, 1, 1, 0, 0, 0)
diff --git a/app/modules/documents/local_agent_runtime/erp_local_agent/__init__.py b/app/modules/documents/local_agent_runtime/erp_local_agent/__init__.py
index 644ec6e..3a4b3fc 100644
--- a/app/modules/documents/local_agent_runtime/erp_local_agent/__init__.py
+++ b/app/modules/documents/local_agent_runtime/erp_local_agent/__init__.py
@@ -1,2 +1,2 @@
-__version__ = "1.26.16"
+__version__ = "1.26.17"
 AGENT_NAME = "ERP Local Agent"
diff --git a/app/modules/documents/local_agent_runtime/erp_local_agent/commands.py b/app/modules/documents/local_agent_runtime/erp_local_agent/commands.py
index 73ba1d3..d5033f2 100644
--- a/app/modules/documents/local_agent_runtime/erp_local_agent/commands.py
+++ b/app/modules/documents/local_agent_runtime/erp_local_agent/commands.py
@@ -179,6 +179,8 @@ class AgentCommandProcessor:
                 result = self._post_it_depreciation(payload)
             elif action == "accounting_mirror_status":
                 result = self._accounting_mirror_status(payload)
+            elif action == "accounting_mirror_list":
+                result = self._accounting_mirror_list(payload)
             elif action == "accounting_mirror_sync":
                 result = self._accounting_mirror_sync(payload)
             elif action == "accounting_full_export_start":
@@ -4192,6 +4194,65 @@ class AgentCommandProcessor:
             "financial_year_to": fy_to.isoformat(),
         }
 
+    def _accounting_mirror_list(self, payload: dict[str, Any]) -> dict[str, Any]:
+        """Discover already-created FY mirrors for one client without relying on Tally names.
+
+        This scans only the canonical Storage Node hierarchy and returns file metadata
+        needed by the ERP mirror registry. No mirror is modified.
+        """
+        import sqlite3 as _sqlite3
+
+        client_id = int(payload.get("client_id") or 0)
+        if client_id <= 0:
+            raise ValueError("client_id is required.")
+        filename = f"client_{client_id:08d}.act"
+        items: list[dict[str, Any]] = []
+        pattern = f"FY*/Clients/*/*/Accounting/{filename}"
+        for path in sorted(self.store.storage_root.glob(pattern)):
+            if not path.is_file():
+                continue
+            try:
+                relative = path.parent.relative_to(self.store.storage_root).as_posix()
+            except Exception:
+                continue
+            first = relative.split("/", 1)[0]
+            fy = first[2:] if first.upper().startswith("FY") else ""
+            if not re.fullmatch(r"\d{4}-\d{2}", fy):
+                continue
+            company: dict[str, Any] = {}
+            voucher_period = {"from_date": "", "to_date": ""}
+            ready = False
+            try:
+                db = _sqlite3.connect(path, timeout=15)
+                db.row_factory = _sqlite3.Row
+                try:
+                    row = db.execute("SELECT * FROM company_master ORDER BY synced_at DESC LIMIT 1").fetchone()
+                    company = dict(row) if row else {}
+                    period = db.execute("SELECT MIN(voucher_date) AS from_date, MAX(voucher_date) AS to_date FROM voucher").fetchone()
+                    if period:
+                        voucher_period = dict(period)
+                    ready = bool(company)
+                finally:
+                    db.close()
+            except Exception:
+                ready = False
+            items.append({
+                "client_id": client_id,
+                "financial_year": fy,
+                "accounting_relative_dir": relative,
+                "accounting_db_path": str(path),
+                "company_name": str(company.get("company_name") or "").strip(),
+                "tally_guid": str(company.get("company_guid") or "").strip(),
+                "mirror": {
+                    "ready": ready,
+                    "path": str(path),
+                    "size_bytes": path.stat().st_size,
+                    "company": company,
+                    "voucher_period": voucher_period,
+                },
+            })
+        return {"mirrors": items, "count": len(items), "agent": self._agent_info()}
+
     def _accounting_mirror_status(self, payload: dict[str, Any]) -> dict[str, Any]:
         client_id = int(payload.get("client_id") or 0)
         if client_id <= 0:
@@ -4248,6 +4309,10 @@ class AgentCommandProcessor:
             "job_id": job_id, "status": "queued", "percent": 1,
             "stage": "Queued", "message": "Full Accounting Export queued on the Local Agent.",
             "client_id": client_id, "company_name": company_name, "tally_guid": tally_guid,
+            "financial_year": str(payload.get("financial_year") or "").strip(),
+            "accounting_relative_dir": str(payload.get("accounting_relative_dir") or "").strip(),
+            "requested_by_user_id": requested_by,
+            "replacement_requested": bool(payload.get("replacement_requested")),
             "date_from": date_from, "date_to": date_to, "rows": {},
             "started_at_utc": now, "updated_at_utc": now, "finished_at_utc": "",
             "error": "", "mirror_db_path": "", "accounting_db_path": str(self.store.db_path(client_id)),