KR 721 then SQ 709 at Bangkok
Siem Reap → Bangkok → Singapore
Timetable, Bangkok time
17:05KR 721 from Siem Reap at the gate
15:45SQ 709 to Singapore leaves the gate
22 h 40 apart on the timetable, overnight
SQ 709 leaves 22 h 40 after KR 721 arrives on the timetable: more than half a day, so not a connection we count.