BA 669 then BA 11 at Heathrow
Marrakesh → London → Singapore
Timetable, London time
20:45BA 669 from Marrakesh at the gate
18:45BA 11 to Singapore leaves the gate
22 h apart on the timetable, overnight
BA 11 leaves 22 h after BA 669 arrives on the timetable: more than half a day, so not a connection we count.