Remember the alert about the incoming missile in Hawaii that turned out to be nonsense? This <https://arstechnica.com/information-technology/2018/01/the-interface-to-send-out-a-missile-alert-in-hawaii-is-as-expected-quite-bad/> is apparently what the user interface looks like for the system that sends out both test and genuine alerts. It looks like a web page with a random assortment of links. Just off the top of my head, not claiming to be a UI expert here, but I would have a big title across the top of the screen saying either “TEST MODE” or “LIVE MODE” (the latter red, and blinking). Then have a single set of options below, appropriate to the active mode. Even go one better, and do what Japanese railway locomotive drivers do as they see signs at the side of the track: say out loud what the signs mean, before taking appropriate action.