AA 3539 then UA 5191 at O'Hare
Moline → Chicago → Lancaster
Timetable, Chicago time
12:36AA 3539 from Moline at the gate
08:50UA 5191 to Lancaster leaves the gate
20 h 14 apart on the timetable, overnight
UA 5191 leaves 20 h 14 after AA 3539 arrives on the timetable: more than half a day, so not a connection we count.