BA 349 then BA 360 at Heathrow
Nice → London → Lyon
Timetable, London time
21:05BA 349 from Nice at the gate
14:45BA 360 to Lyon leaves the gate
17 h 40 apart on the timetable, overnight
BA 360 leaves 17 h 40 after BA 349 arrives on the timetable: more than half a day, so not a connection we count.