UA 5191 then UA 4603 at Houston
Oklahoma City → Houston → Huntsville
Timetable, Houston time
09:30UA 5191 from Oklahoma City at the gate
08:00UA 4603 to Huntsville leaves the gate
22 h 30 apart on the timetable, overnight
UA 4603 leaves 22 h 30 after UA 5191 arrives on the timetable: more than half a day, so not a connection we count.