UA 516 then CA 3174 at O'Hare
Atlanta → Chicago → Guangzhou
Timetable, Chicago time
16:50UA 516 from Atlanta at the gate
13:40CA 3174 to Guangzhou leaves the gate
20 h 50 apart on the timetable, overnight
CA 3174 leaves 20 h 50 after UA 516 arrives on the timetable: more than half a day, so not a connection we count.