UO 251 then CX 500 at Hong Kong
Sanya → Hong Kong → Tokyo Narita
Timetable, Hong Kong time
22:25UO 251 from Sanya at the gate
15:25CX 500 to Tokyo Narita leaves the gate
17 h apart on the timetable, overnight
CX 500 leaves 17 h after UO 251 arrives on the timetable: more than half a day, so not a connection we count.