Setup mode is for a unit you can still reach: it's online now, and you know something is about to change — it's moving to another store, or the store is replacing its router on Tuesday.
The command is delivered the next time the unit checks in. It then opens its setup network while staying on its current connection and continuing to report, so nothing goes dark while you work.
- The request expires by itself if nobody acts on it, so a forgotten one doesn't sit open indefinitely.
- You can cancel before the unit picks it up.
- A unit in setup mode doesn't trigger disconnected warnings — it's meant to be there.
A Wi-Fi unit whose store changed its password recovers on its own now: it recognizes an authentication failure, offers setup mode, and keeps offering it — no site visit and no factory reset. Cellular units are unaffected by store network changes entirely.