KE 852 then 7C 2515 at Incheon
Beijing Capital → Seoul → Chiang Mai
Timetable, Seoul time
21:55KE 852 from Beijing Capital at the gate
19:157C 2515 to Chiang Mai leaves the gate
21 h 20 apart on the timetable, overnight
7C 2515 leaves 21 h 20 after KE 852 arrives on the timetable: more than half a day, so not a connection we count.