In order to improve the handling of backports (3 stable releases means x3 process amplification) and to focus attention on the ones really requiring thorough reviews, what about using a label to indicate that the backport was conflict-less (e.g.: "clean-backport")? 

It could start as a manual action, but if useful it could also be easily automated with a Github Action or directly from the ceph-backport script.

Additionally, adding a size label (XL, L, M, S, ...) might also help everyone quickly understand the complexity and/or when searching PRs in Github.

These are just 2 things we may start doing right now without much effort needed. Further improvements might be launching the "ceph-backport" script directly from the BackportBot or syncing Github-Redmine to deal with the backporting paperwork.

What do you think?