set default for ignore_overwritten_missing_references to true as that
matches unextended reclass closest
diff --git a/reclass/defaults.py b/reclass/defaults.py
index 9fbb478..4c20795 100644
--- a/reclass/defaults.py
+++ b/reclass/defaults.py
@@ -22,7 +22,7 @@
 OPT_IGNORE_CLASS_NOTFOUND_REGEXP = ['.*']
 OPT_IGNORE_CLASS_NOTFOUND_WARNING = True
 
-OPT_IGNORE_OVERWRITTEN_MISSING_REFERENCES = False
+OPT_IGNORE_OVERWRITTEN_MISSING_REFERENCES = True
 
 OPT_ALLOW_SCALAR_OVER_DICT = False
 OPT_ALLOW_SCALAR_OVER_LIST = False