fix(roi): normalize scheduler timestamps to UTC

litellm/proxy/management_endpoints/roi_calculator_endpoints.py

@@ -549,7 +549,11 @@ def _next_update(settings: ROISettings, status: ROISyncStatus, report: ROIReport
     ):
         return None
     anchor: Final = status.finished_at or status.started_at or report["synced_at"]
-    return datetime.fromisoformat(anchor.replace("Z", "+00:00")) + timedelta(minutes=settings.update_interval_minutes)
+    parsed: Final = datetime.fromisoformat(anchor.replace("Z", "+00:00"))
+    utc_anchor: Final = (
+        parsed.replace(tzinfo=timezone.utc) if parsed.tzinfo is None else parsed.astimezone(timezone.utc)
+    )
+    return utc_anchor + timedelta(minutes=settings.update_interval_minutes)
 
 
 async def run_scheduled_sync() -> None:

litellm/proxy/roi_calculator/sync_store.py

@@ -1,4 +1,4 @@
-from datetime import datetime
+from datetime import datetime, timezone
 from types import MappingProxyType
 from typing import Final, Protocol, cast  # noqa: TID251 - PrismaWrapper dynamically delegates database methods
 
@@ -117,7 +117,7 @@ class SyncStore:
                     {
                         "running": False,
                         "phase": "error",
-                        "finished_at": rows[0].last_run_at.isoformat(),
+                        "finished_at": rows[0].last_run_at.replace(tzinfo=timezone.utc).isoformat(),
                         "stage": "Sync interrupted",
                         "error": "The worker stopped responding. Run analysis again to resume saved estimates.",
                     }

tests/integration/database/test_roi_sync_store.py

@@ -72,7 +72,18 @@ async def test_roi_cache_survives_scope_changes_and_uses_writer(monkeypatch: pyt
             ) == ("roi_calculator_pull_new", "roi_calculator_pull_outside-window")
             assert not await store.acquire("scheduled", running, 1440)
             assert await store.acquire("manual", running)
-            assert await store.finish("manual", complete, empty)
+            write_rows(
+                "UPDATE \"LiteLLM_Config\" SET last_run_at = NOW() - INTERVAL '2 minutes' WHERE param_name = %s",
+                ("roi_calculator_sync",),
+                database_url=writer_url,
+            )
+            expired: Final = await store.status()
+            assert expired is not None and expired.phase == "error" and expired.finished_at is not None
+            assert datetime.fromisoformat(expired.finished_at).tzinfo == timezone.utc
+            assert not await store.heartbeat("manual", running)
+            assert await store.acquire("replacement", running)
+            assert not await store.finish("manual", complete, empty)
+            assert await store.finish("replacement", complete, empty)
             assert (
                 len(
                     read_rows(

tests/unit/proxy/management_endpoints/test_roi_calculator_endpoints.py

@@ -1,5 +1,6 @@
 import json
 from collections.abc import Mapping
+from datetime import datetime, timezone
 from types import MappingProxyType
 from typing import Final, cast
 
@@ -12,11 +13,13 @@ from litellm.proxy._types import LitellmUserRoles, UserAPIKeyAuth
 from litellm.proxy.auth.user_api_key_auth import user_api_key_auth
 from litellm.proxy.management_endpoints.roi_calculator_endpoints import (
     _estimator_models_from_deployments,
+    _next_update,
     get_roi_config_repository,
     router,
 )
 from litellm.proxy.roi_calculator.estimator import estimator_options
-from litellm.types.roi_calculator import ROISettings
+from litellm.proxy.roi_calculator.sample import sample_report
+from litellm.types.roi_calculator import ROISettings, ROISyncStatus
 
 _JSON_HEADERS: Final = MappingProxyType({"content-type": "application/json"})
 
@@ -187,3 +190,22 @@ def test_sample_preview_does_not_change_live_settings_or_report() -> None:
 def test_schedule_rejects_intervals_under_five_minutes(interval: float) -> None:
     client: Final = _client(LitellmUserRoles.PROXY_ADMIN, _ConfigRepository())
     assert client.put("/roi-calculator/settings", json={"update_interval_minutes": interval}).status_code == 422
+
+
+@pytest.mark.parametrize("anchor", ("2026-09-30T12:00:00", "2026-09-30T12:00:00Z", "2026-09-30T14:00:00+02:00"))
+def test_schedule_normalizes_legacy_and_offset_timestamps(anchor: str) -> None:
+    settings: Final = ROISettings(repos=("example/repo",), estimator_model="estimator", update_interval_minutes=60)
+    status: Final = ROISyncStatus(
+        running=False,
+        phase="error",
+        stage="Interrupted",
+        done=0,
+        total=0,
+        estimated=0,
+        reused=0,
+        needs_attention=0,
+        error=None,
+        finished_at=anchor,
+    )
+    report: Final = sample_report(datetime(2026, 9, 30, tzinfo=timezone.utc))
+    assert _next_update(settings, status, report) == datetime(2026, 9, 30, 13, tzinfo=timezone.utc)