Oh wow, just going into the "should I shutdown" menu also goes into pre-boot lock state? I didn't know that.

It doesn't reenter a BFU state, but it requires a passcode for the next unlock.

	▲	snuxoll 20 minutes ago \| parent [-]
		It's close enough, because (most of) the encryption keys are wiped from memory every time the device is locked, and this action makes the secure enclave require PIN authentication to release them again.