UA 3572 then LF 7920 at O'Hare
Cleveland → Chicago → BKX
Timetable, Chicago time
16:55UA 3572 from Cleveland at the gate
13:45LF 7920 to BKX leaves the gate
20 h 50 apart on the timetable, overnight
LF 7920 leaves 20 h 50 after UA 3572 arrives on the timetable: more than half a day, so not a connection we count.