Bibs that are deleted from the catalog are in some cases failing to be entered in the ole_ds_deleted_bib_t table. It isn't clear what actions are causing this problem. It could be a particular code path that is not covered, or it could be that some code that handles exceptions may be failing to register the deletes. A good place to look would be in batch delete operations. I am making this a blocker because it is causing Vufind to become out of sync with the the OLE database.