One master file. Every platform version is a crop, not a redesign.

On Nov 2 our cover rollout went wrong because each platform got its own version instead of one approved file, and alignment was eyeballed instead of measured against where the profile picture actually sits. Versions raced each other and a superseded design kept landing. Now the rule is locked: one master file, recorded before any platform work, every version is a crop or resize of that master only, alignment measured from the visitor view, one surface at a time, verified live before we call it done.