UA 3236 then UA 4307 at Houston
Mc Allen → Houston → Mobile
Timetable, Houston time
20:10UA 3236 from Mc Allen at the gate
14:35UA 4307 to Mobile leaves the gate
18 h 25 apart on the timetable, overnight
UA 4307 leaves 18 h 25 after UA 3236 arrives on the timetable: more than half a day, so not a connection we count.