WB 700 then BA 389 at Brussels
Kigali → Brussels → London Heathrow
Timetable, Brussels time
17:00WB 700 from Kigali at the gate
11:25BA 389 to London Heathrow leaves the gate
18 h 25 apart on the timetable, overnight
BA 389 leaves 18 h 25 after WB 700 arrives on the timetable: more than half a day, so not a connection we count.