BA 753 then BA 1394 at Heathrow
Geneva → London → Belfast City
Timetable, London time
10:00BA 753 from Geneva at the gate
09:20BA 1394 to Belfast City leaves the gate
23 h 20 apart on the timetable, overnight
BA 1394 leaves 23 h 20 after BA 753 arrives on the timetable: more than half a day, so not a connection we count.