diff --git a/graphiti_core/prompts/extract_edge_dates.py b/graphiti_core/prompts/extract_edge_dates.py
index 18164467..a39e927b 100644
--- a/graphiti_core/prompts/extract_edge_dates.py
+++ b/graphiti_core/prompts/extract_edge_dates.py
@@ -82,6 +82,7 @@ def v1(context: dict[str, Any]) -> list[Message]:
             7. If only a date is mentioned without a specific time, use 00:00:00 (midnight) for that date.
             8. If only year is mentioned, use January 1st of that year at 00:00:00.
             9. Always include the time zone offset (use Z for UTC if no specific time zone is mentioned).
+            10. A fact discussing that something is no longer true should have a valid_at according to when the negated fact became true.
             """,
         ),
     ]
diff --git a/graphiti_core/utils/maintenance/community_operations.py b/graphiti_core/utils/maintenance/community_operations.py
index 4d30544e..15bab425 100644
--- a/graphiti_core/utils/maintenance/community_operations.py
+++ b/graphiti_core/utils/maintenance/community_operations.py
@@ -101,9 +101,7 @@ def label_propagation(projection: dict[str, list[Neighbor]]) -> list[list[str]]:
             ]
 
             community_lst.sort(reverse=True)
-            candidate_rank, community_candidate = (
-                community_lst[0] if community_lst else (0, -1)
-            )
+            candidate_rank, community_candidate = community_lst[0] if community_lst else (0, -1)
             if community_candidate != -1 and candidate_rank > 1:
                 new_community = community_candidate
             else: