U2 8306 then VY 7613 at Gatwick
Milan → London → Barcelona
Timetable, London time
20:55U2 8306 from Milan at the gate
15:25VY 7613 to Barcelona leaves the gate
18 h 30 apart on the timetable, overnight
VY 7613 leaves 18 h 30 after U2 8306 arrives on the timetable: more than half a day, so not a connection we count.