FR 270 then BA 485 at Barcelona
Milan → Barcelona → London Heathrow
Timetable, Barcelona time
17:45FR 270 from Milan at the gate
17:30BA 485 to London Heathrow leaves the gate
23 h 45 apart on the timetable, overnight
BA 485 leaves 23 h 45 after FR 270 arrives on the timetable: more than half a day, so not a connection we count.