diff --git a/backend/pashub_fetcher/pashub_service.py b/backend/pashub_fetcher/pashub_service.py
index b3302fd9..2b8f0926 100644
--- a/backend/pashub_fetcher/pashub_service.py
+++ b/backend/pashub_fetcher/pashub_service.py
@@ -1,6 +1,6 @@
 import os
 from datetime import datetime, timezone
-from typing import List, NamedTuple, Optional, cast
+from typing import Callable, List, NamedTuple, Optional, cast
 
 from backend.app.db.connection import db_session
 from backend.app.db.models.uploaded_file import (
@@ -11,7 +11,7 @@ from backend.app.db.models.uploaded_file import (
 from backend.documents_parser.db_writer import save_epc_property_data
 from backend.documents_parser.parser import parse_site_notes_pdf
 from backend.pashub_fetcher.core_files import get_file_type_string
-from backend.pashub_fetcher.pashub_client import PashubClient
+from backend.pashub_fetcher.pashub_client import PashubClient, UnauthorizedError
 from backend.pashub_fetcher.pashub_to_ara_trigger_request import (
     PashubToAraTriggerRequest,
 )
@@ -36,10 +36,13 @@ class PashubService:
         pashub_client: PashubClient,
         sharepoint_client: DomnaSharepointClient,
         s3_bucket: str,
+        coordination_client_factory: Optional[Callable[[], PashubClient]] = None,
     ) -> None:
         self._pashub_client = pashub_client
         self._sharepoint_client = sharepoint_client
         self._s3_bucket = s3_bucket
+        self._coordination_client_factory = coordination_client_factory
+        self._coordination_client: Optional[PashubClient] = None
 
     def run(self, request: PashubToAraTriggerRequest) -> List[str]:
         job_id = request.pashub_job_id
diff --git a/backend/pashub_fetcher/tests/test_pashub_service.py b/backend/pashub_fetcher/tests/test_pashub_service.py
index 2aff416b..44c6af1a 100644
--- a/backend/pashub_fetcher/tests/test_pashub_service.py
+++ b/backend/pashub_fetcher/tests/test_pashub_service.py
@@ -1,8 +1,8 @@
-from typing import Optional
+from typing import Callable, Optional
 from unittest.mock import MagicMock, call, patch
 
 
-from backend.pashub_fetcher.pashub_client import PashubClient
+from backend.pashub_fetcher.pashub_client import PashubClient, UnauthorizedError
 from backend.pashub_fetcher.pashub_service import PashubService
 from backend.pashub_fetcher.pashub_to_ara_trigger_request import (
     PashubToAraTriggerRequest,
@@ -31,11 +31,13 @@ def make_service(
     pashub_client: Optional[PashubClient] = None,
     sharepoint_client: Optional[DomnaSharepointClient] = None,
     s3_bucket: str = "test-bucket",
+    coordination_client_factory: Optional[Callable[[], PashubClient]] = None,
 ) -> PashubService:
     return PashubService(
         pashub_client=pashub_client or MagicMock(spec=PashubClient),
         sharepoint_client=sharepoint_client or MagicMock(spec=DomnaSharepointClient),
         s3_bucket=s3_bucket,
+        coordination_client_factory=coordination_client_factory,
     )
 
 
@@ -225,6 +227,36 @@ def test_run_parses_and_saves_site_notes_for_rd_sap_site_note_file() -> None:
 # ---------------------------------------------------------------------------
 
 
+# ---------------------------------------------------------------------------
+# run(): coordination fallback
+# ---------------------------------------------------------------------------
+
+
+def test_run_uses_coordination_client_when_pas_401_on_uprn_lookup() -> None:
+    pas_client = MagicMock(spec=PashubClient)
+    pas_client.get_uprn_by_job_id.side_effect = UnauthorizedError()
+
+    coord_client = MagicMock(spec=PashubClient)
+    coord_client.get_uprn_by_job_id.return_value = "99999"
+    coord_client.get_core_evidence_files_by_job_id.return_value = ["/tmp/a.pdf"]
+
+    factory = MagicMock(return_value=coord_client)
+
+    service = make_service(pashub_client=pas_client, coordination_client_factory=factory)
+
+    with (
+        patch("backend.pashub_fetcher.pashub_service.upload_file_to_s3"),
+        patch("backend.pashub_fetcher.pashub_service.db_session"),
+        patch("backend.pashub_fetcher.pashub_service.os.remove"),
+    ):
+        result = service.run(make_request())
+
+    assert result == ["/tmp/a.pdf"]
+    coord_client.get_uprn_by_job_id.assert_called_once()
+    coord_client.get_core_evidence_files_by_job_id.assert_called_once()
+    assert factory.call_count == 1
+
+
 def test_run_warns_and_continues_when_site_notes_parsing_fails() -> None:
     mock_client = MagicMock(spec=PashubClient)
     mock_client.get_uprn_by_job_id.return_value = None