IB 5355 then U2 2324 at Barcelona
Milan → Barcelona → London Luton
Timetable, Barcelona time
14:55IB 5355 from Milan at the gatealso LL 5355, VY 6043
10:20U2 2324 to London Luton leaves the gate
19 h 25 apart on the timetable, overnight
U2 2324 leaves 19 h 25 after IB 5355 arrives on the timetable: more than half a day, so not a connection we count.