AA 2230 then UA 4312 at Houston
Miami → Houston → Mobile
Timetable, Houston time
23:58AA 2230 from Miami at the gate
20:26UA 4312 to Mobile leaves the gate
20 h 28 apart on the timetable, overnight
UA 4312 leaves 20 h 28 after AA 2230 arrives on the timetable: more than half a day, so not a connection we count.