BA 669 then UL 504 at Heathrow
Marrakesh → London → Colombo
Timetable, London time
20:45BA 669 from Marrakesh at the gate
20:40UL 504 to Colombo leaves the gate
23 h 55 apart on the timetable, overnight
UL 504 leaves 23 h 55 after BA 669 arrives on the timetable: more than half a day, so not a connection we count.