AA 928 then UA 4550 at O'Hare
Miami → Chicago → Columbia Regional
Timetable, Chicago time
19:49AA 928 from Miami at the gate
19:45UA 4550 to Columbia Regional leaves the gate
23 h 56 apart on the timetable, overnight
UA 4550 leaves 23 h 56 after AA 928 arrives on the timetable: more than half a day, so not a connection we count.