U2 802 then U2 8065 at Gatwick
Belfast City → London → Barcelona
Timetable, London time
11:45U2 802 from Belfast City at the gate
09:10U2 8065 to Barcelona leaves the gate
21 h 25 apart on the timetable, overnight
U2 8065 leaves 21 h 25 after U2 802 arrives on the timetable: more than half a day, so not a connection we count.