FR 7538 then BA 483 at Barcelona
Milan → Barcelona → London Heathrow
Timetable, Barcelona time
00:40FR 7538 from Milan at the gate
18:10BA 483 to London Heathrow leaves the gate
17 h 30 apart on the timetable
BA 483 leaves 17 h 30 after FR 7538 arrives on the timetable: more than half a day, so not a connection we count.