BA 345 then BA 374 at Heathrow
Nice → London → Toulouse
Timetable, London time
17:15BA 345 from Nice at the gate
16:10BA 374 to Toulouse leaves the gate
22 h 55 apart on the timetable, overnight
BA 374 leaves 22 h 55 after BA 345 arrives on the timetable: more than half a day, so not a connection we count.