U2 802 then U2 831 at Gatwick
Belfast City → London → Belfast International
Timetable, London time
20:55U2 802 from Belfast City at the gate
18:05U2 831 to Belfast International leaves the gate
21 h 10 apart on the timetable, overnight
U2 831 leaves 21 h 10 after U2 802 arrives on the timetable: more than half a day, so not a connection we count.