Using forget for the first time - triggering backup triggers a full backup - why?

Hello!

After a while, I caught myself being far behind on the versions. I was running Restic 0.9.6 for an eternity (like a year or probably more) and today I upgraded to 1.13.1 (using restic self-upgrade)

Although, I also then thought let me finally put in place the removal of some of the backups I have.
What I did, was;

restic -r /mnt/backup/my-folder/ forget --keep-within-daily 61d --keep-within-weekly 4m --keep-within-monthly 3y --keep-within-yearly 80y --prune

My output was;

[0:00] 100.00%  339 / 339 files deleted...
339 snapshots have been removed, running prune
loading indexes...
loading all snapshots...
finding data that is still in use for 78 snapshots
[1:44] 100.00%  78 / 78 snapshots...
searching used packs...
collecting packs for deletion and repacking
[0:48] 100.00%  470108 / 470108 packs processed...

to repack:        980076 blobs / 13.596 GiB
this removes:     243623 blobs / 11.424 GiB
to delete:        528891 blobs / 431.274 GiB
total prune:      772514 blobs / 442.698 GiB
remaining:       5291747 blobs / 1.862 TiB
unused size after prune: 66.096 GiB (3.47% of remaining size)

deleting unreferenced packs
[0:00] 100.00%  20 / 20 files deleted...
repacking packs
[3:03] 100.00%  1426 / 1426 packs repacked...
rebuilding index
[0:33] 100.00%  387394 / 387394 packs processed...
deleting obsolete index files
[0:03] 100.00%  922 / 922 files deleted...
removing 83248 old packs
[3:19] 100.00%  83248 / 83248 files deleted...
done

According to what I did on my dry-run, this was what I expected. I also verified by checking the listed snapshots and confirming the dates. So far, so good.

Now I continued to trigger a new backup:

restic -r /mnt/backup/my-folder/ backup /etc /var /opt /home /root /mnt --exclude "/var/www/some-folder" --exclude "/mnt/some-other-folder"

I have been using this same command for a while, only thing that has changed since last night’s automated run, is the restic version.

Now, it plans to do a ~30 hour backup of 1.8TB of data. Did something change in the version that makes previous snapshots incompatible?

[12:37] 0.47%  42202 files 60.01 GB, total 3655112 files 1.811 TiB, 0 errors ETA 31:01:12

Am I doing something wrong?

Thank you!

I am way too impatient, the progress went really quick and completed. I guess that is how it works!