diff --git a/applications/modelling_e2e/handler.py b/applications/modelling_e2e/handler.py
index 55a646676..51c3e8149 100644
--- a/applications/modelling_e2e/handler.py
+++ b/applications/modelling_e2e/handler.py
@@ -210,7 +210,7 @@ def _flush_writes(engine: Engine, writes: list[_PropertyWrite]) -> None:
         # p.is_new rule — readers select one default Plan per property, so a
         # first run under a non-default Scenario must still produce one).
         # Also heals properties left default-less by runs before this rule.
-        have_default: set[int] = uow.plan.property_ids_with_default_plans(
+        pids_with_default: set[int] = uow.plan.property_ids_with_default_plans(
             [w.property_id for w in writes]
         )
         plan_requests = [
@@ -219,7 +219,7 @@ def _flush_writes(engine: Engine, writes: list[_PropertyWrite]) -> None:
                 property_id=w.property_id,
                 scenario_id=w.scenario_id,
                 portfolio_id=w.portfolio_id,
-                is_default=w.is_default or w.property_id not in have_default,
+                is_default=w.is_default or w.property_id not in pids_with_default,
             )
             for w in writes
         ]
diff --git a/repositories/plan/plan_postgres_repository.py b/repositories/plan/plan_postgres_repository.py
index 21540523a..dc3b135a7 100644
--- a/repositories/plan/plan_postgres_repository.py
+++ b/repositories/plan/plan_postgres_repository.py
@@ -47,6 +47,8 @@ class PlanPostgresRepository(PlanRepository):
         )[0]
 
     def property_ids_with_default_plans(self, property_ids: list[int]) -> set[int]:
+        if not property_ids:
+            return set()
         rows = self._session.exec(
             select(col(PlanModel.property_id))
             .distinct()
diff --git a/tests/orchestration/fakes.py b/tests/orchestration/fakes.py
index 52f409693..4c6d323b9 100644
--- a/tests/orchestration/fakes.py
+++ b/tests/orchestration/fakes.py
@@ -212,6 +212,7 @@ class FakePlanRepository(PlanRepository):
 
     def __init__(self) -> None:
         self.saved: dict[tuple[int, int], Plan] = {}
+        self.default_property_ids: set[int] = set()
         self._next_id = 1
 
     def save(
@@ -224,6 +225,8 @@ class FakePlanRepository(PlanRepository):
         is_default: bool,
     ) -> int:
         self.saved[(property_id, scenario_id)] = plan
+        if is_default:
+            self.default_property_ids.add(property_id)
         plan_id = self._next_id
         self._next_id += 1
         return plan_id
@@ -241,9 +244,7 @@ class FakePlanRepository(PlanRepository):
         ]
 
     def property_ids_with_default_plans(self, property_ids: list[int]) -> set[int]:
-        # The fake store does not track defaults; every property reads as
-        # first-time (no default yet).
-        return set()
+        return self.default_property_ids.intersection(property_ids)
 
 
 class _UnsetProductRepo(ProductRepository):