I tried using the backup codes but they didn’t work as they were removed with the above error messages. So if there is a cloud or server issue, it can remove the backup codes as well. Not as durable as I thought.I would be shocked and amazed if the cloud was needed to USE BackupStartCode after it is set.; my bet is that the encrypted key /password sits in the MME local Sync4 memory once it has been set up... Once you have your PAAK enabled, and activated, and backupstartcode set, you should be good no matter what.
otherwise, you could not EVER use the code if you were not in wifi/cell range.
I know for a fact that it worked when I was in the mountains without cell or wifi because I tested what would happen if I used door code, and backup code, as if I lost my phone while hiking. ( I turned phone off, and left trailside a ways away from MME, used door code for entry, and backupstartcode to run....)