BA 773 then A3 605 at Heathrow
Oslo → London → Athens
Timetable, London time
22:00BA 773 from Oslo at the gate
19:00A3 605 to Athens leaves the gate
21 h apart on the timetable, overnight
A3 605 leaves 21 h after BA 773 arrives on the timetable: more than half a day, so not a connection we count.