U2 802 then BA 2656 at Gatwick
Belfast City → London → Alicante
Timetable, London time
20:50U2 802 from Belfast City at the gate
15:40BA 2656 to Alicante leaves the gate
18 h 50 apart on the timetable, overnight
BA 2656 leaves 18 h 50 after U2 802 arrives on the timetable: more than half a day, so not a connection we count.