The Life of a Product Version Diagram

A version is never edited

Every change makes a new numbered version
A fix is a new candidate, not a patch on the old one
Every version stays stored

Approval is earned

Only a version that ran well is approved
Approval does not change production by itself
Production is a separate, deliberate step

Going back is simple

Pick an earlier approved version
Pin it in production, the same way as going forward
The change is recorded like any other