Originally Posted by Manichean
What do you mean by 'full backup'? The only backup mechanism I'm aware of is the metadata backup to OPF, which should only run once for the full library when you install the version introducing that feature.
Sorry for delayed answer, been a bit hectic at work.
Yes, I meant a full OPF backup
Library ->Library Maintenance ->Library Metadata Backup Status
8.12 Showed me 0 to be backed up before installing 8.13.
After upgrade, 1600 books needed backup.
Sunday I installed the new 8.13, and again 1600 books needed backup.
Will look more into it during 8.14 upgrade.