UA 3671 then CA 3174 at O'Hare
Charlotte → Chicago → Guangzhou
Timetable, Chicago time
16:52UA 3671 from Charlotte at the gate
13:40CA 3174 to Guangzhou leaves the gate
20 h 48 apart on the timetable, overnight
CA 3174 leaves 20 h 48 after UA 3671 arrives on the timetable: more than half a day, so not a connection we count.