BA 1399 then SK 806 at Heathrow
Belfast City → London → Oslo
Timetable, London time
16:35BA 1399 from Belfast City at the gate
15:35SK 806 to Oslo leaves the gate
23 h apart on the timetable, overnight
SK 806 leaves 23 h after BA 1399 arrives on the timetable: more than half a day, so not a connection we count.