AA 4504 then UA 5282 at O'Hare
South Bend → Chicago → Lexington
Timetable, Chicago time
18:35AA 4504 from South Bend at the gate
14:50UA 5282 to Lexington leaves the gate
20 h 15 apart on the timetable, overnight
UA 5282 leaves 20 h 15 after AA 4504 arrives on the timetable: more than half a day, so not a connection we count.