BA 349 then QR 8 at Heathrow
Nice → London → Doha
Timetable, London time
21:05BA 349 from Nice at the gate
14:55QR 8 to Doha leaves the gate
17 h 50 apart on the timetable, overnight
QR 8 leaves 17 h 50 after BA 349 arrives on the timetable: more than half a day, so not a connection we count.