AA 423 then CZ 2508 at O'Hare
Washington National → Chicago → Guangzhou
Timetable, Chicago time
21:29AA 423 from Washington National at the gate
19:50CZ 2508 to Guangzhou leaves the gate
22 h 21 apart on the timetable, overnight
CZ 2508 leaves 22 h 21 after AA 423 arrives on the timetable: more than half a day, so not a connection we count.