ZH 8904 then CZ 3639 at Guangzhou
Zhengzhou → Guangzhou → Nantong
Timetable, Guangzhou time
13:55ZH 8904 from Zhengzhou at the gate
13:35CZ 3639 to Nantong leaves the gate
23 h 40 apart on the timetable, overnight
CZ 3639 leaves 23 h 40 after ZH 8904 arrives on the timetable: more than half a day, so not a connection we count.