tl;dr: the scap release process is manual and fiddly and it has recently failed quite a bit, so it's probably time to rethink it.
Currently, scap is deployed to the deployment-prep cluster via a debian package built from the master branch of scap. Once scap devs are happy with that version, master is merged into the release branch where we cut a new debian package for production.
Having two branches with debian folders (master and release) has caused packaging confusion (T183046). Not (manually) bumping the version in master at the same time we upload a new package to production from the release branch causes deployment-prep puppet breakage (T184118). Having the beta package built post-merge has let some scap bugs escape and break other folks workflow in deployment-prep (T184176). We should try to automate and simplify as much of this as possible in light of recent breakage.