BA 585 then BA 640 at Heathrow
Milan Linate → London → Athens
Timetable, London time
21:30BA 585 from Milan Linate at the gate
19:45BA 640 to Athens leaves the gate
22 h 15 apart on the timetable, overnight
BA 640 leaves 22 h 15 after BA 585 arrives on the timetable: more than half a day, so not a connection we count.