15 builders, one castle, zero chaos. Every lesson is a sprint. Every sprint ends with a team review. Unanimous tick = version bump. No consensus = rollback, and that version number has to wait until the team earns it next sprint.
Every change a builder makes is a block on the timeline. Small changes, made often, with your name on them. No mystery edits.
At the end of each sprint the team runs its own meeting and checks the build against the defence plan. Everyone votes.
Unanimous tick? The build is tagged as the next version: v1.1, v1.2, v1.3... That tag is a save point you can always get back to.
No consensus? Roll back to the last tagged version. The failed version number isn't skipped, it just has to wait: the team earns it in the next sprint instead.