tuypi They are related to S3. I had the same issue before, I enabled S3 backups to test and disabled it again then experienced the same error messages filling up my log files.
I spoke to Adam at the time and he suggested running this from your control panel server:
docker exec -it orchd-postgres psql -U enhance
delete from backups where storage_kind = 's3';
It seems as though the info doesn't get removed from the Postgres database when S3 is disabled.
