The release branch for scap has tags for 3.8.10-1.
Instructions available on Wikitech.
There is 1 important change here.
scap (3.8.10-1) unstable; urgency=low * sync-wikiversions - don't do shell expansion -- Tyler Cipriani <tcipriani@wikimedia.org> Tue, 27 Nov 2018 11:40:31 -0700