@roadmr yes your guess is correct. I’d like track “1” for 1.x releases and “2” for 2.x releases.
Reason for this split is that prometheus 2 uses new metric storage format which is not backwards compatible. There are currently no plans to support data migration between prometheus 1 and 2.
Pigeonholing all 1.x under “1” and 2.x under “2” will work great. The project currently does not have LTS-style releases so users have to upgrade to latest version for bugfixes and new features. I started building prometheus snaps at v1.1.1 and upgrades always worked, it’s currently on 1.7.1