diff --git a/util/ace/update_tools.py b/util/ace/update_tools.py
index b81b128..c708276 100644
--- a/util/ace/update_tools.py
+++ b/util/ace/update_tools.py
@@ -77,7 +77,8 @@ def _seed_from_offline(local: Path, offline_name: str, log_fn) -> bool:
         return local.is_file()
     local.parent.mkdir(parents=True, exist_ok=True)
     shutil.copy2(src, local)
-    _log(f"Synced {offline_name} from offline bundle", log_fn)
+    if log_fn:
+        _log(f"Synced {offline_name} from offline bundle", log_fn)
     return True
 
 
diff --git a/util/forge/update_tools.py b/util/forge/update_tools.py
index a50b917..4a3ad60 100644
--- a/util/forge/update_tools.py
+++ b/util/forge/update_tools.py
@@ -109,7 +109,8 @@ def _seed_from_offline(engine: str, log_fn) -> bool:
     if not offline.is_file():
         return False
     shutil.copy2(offline, dest)
-    _log(f"Using offline bundled {dest.name}", log_fn)
+    if log_fn:
+        _log(f"Using offline bundled {dest.name}", log_fn)
     return True