I understood the original message.
During Covid, the California Service Center (CSC), where petitions are adjudicated would hold approved petitions until the NVC requested them. They may still be doing that. In other words, if the backup is further along the chain at the consulate, there is no rush to send approved petitions to NVC. If they're going to just sit there, they can sit at the CSC.
Just a thought, since it seems to be a pattern, rather than isolated.