AA 3239 then LF 7920 at O'Hare
Pittsburgh → Chicago → BKX
Timetable, Chicago time
16:54AA 3239 from Pittsburgh at the gate
13:45LF 7920 to BKX leaves the gate
20 h 51 apart on the timetable, overnight
LF 7920 leaves 20 h 51 after AA 3239 arrives on the timetable: more than half a day, so not a connection we count.