diff --git a/src/sentry/workflow_engine/handlers/condition/issue_priority_deescalating_handler.py b/src/sentry/workflow_engine/handlers/condition/issue_priority_deescalating_handler.py
index a8b2e28006fd..f3f217c92ae1 100644
--- a/src/sentry/workflow_engine/handlers/condition/issue_priority_deescalating_handler.py
+++ b/src/sentry/workflow_engine/handlers/condition/issue_priority_deescalating_handler.py
@@ -13,14 +13,7 @@
 class IssuePriorityDeescalatingConditionHandler(DataConditionHandler[WorkflowEventData]):
     group = DataConditionHandler.Group.ACTION_FILTER
     subgroup = DataConditionHandler.Subgroup.ISSUE_ATTRIBUTES
-    comparison_json_schema = {
-        "anyOf": [
-            {"type": "integer", "enum": [*PriorityLevel]},
-            # Temporary compatibility for the automation builder's broken default.
-            # Remove after ISWF-3453 is complete and stored comparisons are cleaned up.
-            {"type": "boolean", "const": True},
-        ]
-    }
+    comparison_json_schema = {"type": "integer", "enum": [*PriorityLevel]}
 
     @staticmethod
     def evaluate_value(event_data: WorkflowEventData, comparison: Any) -> bool:
@@ -39,8 +32,8 @@ def evaluate_value(event_data: WorkflowEventData, comparison: Any) -> bool:
         # use this to determine if we've breached the comparison priority before
         highest_seen_priority = open_period.data.get("highest_seen_priority", current_priority)
 
-        # Preserve the current behavior for the automation builder's broken default.
-        # Remove this compatibility path after ISWF-3453 is complete.
+        # Existing rows may still contain the automation builder's previous boolean default.
+        # Keep evaluation compatible until those rows are migrated to a priority threshold.
         if comparison is True:
             return group.status == GroupStatus.RESOLVED
 
diff --git a/tests/sentry/workflow_engine/endpoints/validators/test_base_data_condition.py b/tests/sentry/workflow_engine/endpoints/validators/test_base_data_condition.py
index 212b9964fe9d..0a7502be3346 100644
--- a/tests/sentry/workflow_engine/endpoints/validators/test_base_data_condition.py
+++ b/tests/sentry/workflow_engine/endpoints/validators/test_base_data_condition.py
@@ -91,7 +91,7 @@ def test_issue_priority_deescalating(self) -> None:
             self._validator(Condition.ISSUE_PRIORITY_DEESCALATING, PriorityLevel.HIGH).is_valid()
             is True
         )
-        assert self._validator(Condition.ISSUE_PRIORITY_DEESCALATING, True).is_valid() is True
+        assert self._validator(Condition.ISSUE_PRIORITY_DEESCALATING, True).is_valid() is False
         assert self._validator(Condition.ISSUE_PRIORITY_DEESCALATING, False).is_valid() is False
         assert self._validator(Condition.ISSUE_PRIORITY_DEESCALATING, 100).is_valid() is False
 
diff --git a/tests/sentry/workflow_engine/handlers/condition/test_issue_priority_deescalating_handler.py b/tests/sentry/workflow_engine/handlers/condition/test_issue_priority_deescalating_handler.py
index 9211c38b7d9c..8f70db15a659 100644
--- a/tests/sentry/workflow_engine/handlers/condition/test_issue_priority_deescalating_handler.py
+++ b/tests/sentry/workflow_engine/handlers/condition/test_issue_priority_deescalating_handler.py
@@ -59,12 +59,6 @@ def setUp(self) -> None:
             condition_result=True,
             condition_group=dc_critical.condition_group,
         )
-        self.deescalating_dc_boolean = self.create_data_condition(
-            comparison=True,
-            type=self.condition,
-            condition_result=True,
-            condition_group=dc_critical.condition_group,
-        )
 
     def update_group_and_open_period(self, priority: PriorityLevel) -> None:
         self.group.update(priority=priority)
@@ -107,12 +101,21 @@ def test_critical(self) -> None:
         self.assert_passes(self.deescalating_dc_critical, self.event_data)
 
     def test_boolean_comparison_preserves_existing_behavior(self) -> None:
+        boolean_condition = self.create_data_condition(
+            comparison=DetectorPriorityLevel.HIGH,
+            type=self.condition,
+            condition_result=True,
+            condition_group=self.deescalating_dc_critical.condition_group,
+        )
+        type(boolean_condition).objects.filter(id=boolean_condition.id).update(comparison=True)
+        boolean_condition.refresh_from_db()
+
         self.update_group_and_open_period(priority=PriorityLevel.HIGH)
         self.update_group_and_open_period(priority=PriorityLevel.MEDIUM)
-        self.assert_does_not_pass(self.deescalating_dc_boolean, self.event_data)
+        self.assert_does_not_pass(boolean_condition, self.event_data)
 
         self.group.update(status=GroupStatus.RESOLVED)
-        self.assert_passes(self.deescalating_dc_boolean, self.event_data)
+        self.assert_passes(boolean_condition, self.event_data)
 
     @override_options(
         {"workflow_engine.group.type_id.open_periods_type_denylist": [DEFAULT_TYPE_ID]}