BA 753 then BA 594 at Heathrow
Geneva → London → Venezia
Timetable, London time
10:00BA 753 from Geneva at the gate
08:05BA 594 to Venezia leaves the gate
22 h 05 apart on the timetable, overnight
BA 594 leaves 22 h 05 after BA 753 arrives on the timetable: more than half a day, so not a connection we count.