BA 773 then BA 496 at Heathrow
Oslo → London → Barcelona
Timetable, London time
20:00BA 773 from Oslo at the gate
19:20BA 496 to Barcelona leaves the gate
23 h 20 apart on the timetable, overnight
BA 496 leaves 23 h 20 after BA 773 arrives on the timetable: more than half a day, so not a connection we count.