@retro: MiniClock doesn't care/know about *any* of your non-MiniClock settings (if you forget about those it obviously tracks, like frontlight level or the nightmode status). It lives entirely in its own little bubble world.
So, if you want to disable it, you'll have to... disable it

.
If you only want to disable it *under certain circumstances*, then you're SoL

.
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Incidentally, that answers Jon's... let's say "query". You could run MiniClock with basically nothing running on the device, it'd still show a clock on swipe/button press ^^. So, no, it doesn't care about the FW version.
(Technical note: emphasis on *could*. It does currently require nickel to be running as a sanity check).