@ts678 - thank you so much for the detailed response. It’s good to know that folks are tracking the issue.
In my case, this backup is run by an always-on machine targeting a remote destination (Backblaze B2).
I just ran the delete operation on the offending version which has let the backup start running again normally.
For now, I’m not going to make any of the suggested changes because this is the first time I’ve hit this issue. I’ll keep things running as-is and report back if I hit the issue again.