BA 1401 then BA 722 at Heathrow
Belfast City → London → Zurich
Timetable, London time
18:25BA 1401 from Belfast City at the gate
17:20BA 722 to Zurich leaves the gate
22 h 55 apart on the timetable, overnight
BA 722 leaves 22 h 55 after BA 1401 arrives on the timetable: more than half a day, so not a connection we count.