FB 851 then BA 1308 at Heathrow
Sofia → London → Aberdeen
Timetable, London time
16:45FB 851 from Sofia at the gate
12:55BA 1308 to Aberdeen leaves the gate
20 h 10 apart on the timetable, overnight
BA 1308 leaves 20 h 10 after FB 851 arrives on the timetable: more than half a day, so not a connection we count.