FR 270 then BA 483 at Barcelona
Milan → Barcelona → London Heathrow
Timetable, Barcelona time
17:45FR 270 from Milan at the gate
15:30BA 483 to London Heathrow leaves the gate
21 h 45 apart on the timetable, overnight
BA 483 leaves 21 h 45 after FR 270 arrives on the timetable: more than half a day, so not a connection we count.