BA 893 then BA 59 at Heathrow
Sofia → London → Cape Town
Timetable, London time
22:30BA 893 from Sofia at the gate
22:20BA 59 to Cape Town leaves the gate
23 h 50 apart on the timetable, overnight
BA 59 leaves 23 h 50 after BA 893 arrives on the timetable: more than half a day, so not a connection we count.