KE 852 then ZE 623 at Incheon
Beijing Capital → Seoul → Sapporo
Timetable, Seoul time
21:55KE 852 from Beijing Capital at the gate
14:35ZE 623 to Sapporo leaves the gate
16 h 40 apart on the timetable, overnight
ZE 623 leaves 16 h 40 after KE 852 arrives on the timetable: more than half a day, so not a connection we count.