:add/edit screens, only basic validation (e.g. non-empty) and address-field-specific merchant-provided errors
;M3
:FTU, data validation & error recovery, "update" badge, ready to enable on Nightly-only / Partner / End-to-end User Testing (not riding the trains)
;M4
:P1 telemetry probes, "update" badge, Tab modal widget (maybe do in parallel), UI feature complete, ready for release users, Visual Polish, cc logos
;MVP
:Ride the trains