U2 802 then U2 8309 at Gatwick
Belfast City → London → Milan
Timetable, London time
20:55U2 802 from Belfast City at the gate
16:20U2 8309 to Milan leaves the gate
19 h 25 apart on the timetable, overnight
U2 8309 leaves 19 h 25 after U2 802 arrives on the timetable: more than half a day, so not a connection we count.