BA 1401 then BA 748 at Heathrow
Belfast City → London → Geneva
Timetable, London time
18:15BA 1401 from Belfast City at the gate
17:55BA 748 to Geneva leaves the gate
23 h 40 apart on the timetable, overnight
BA 748 leaves 23 h 40 after BA 1401 arrives on the timetable: more than half a day, so not a connection we count.