BA 423 then BA 346 at Heathrow
Málaga → London → Nice
Timetable, London time
15:00BA 423 from Málaga at the gate
13:25BA 346 to Nice leaves the gate
22 h 25 apart on the timetable, overnight
BA 346 leaves 22 h 25 after BA 423 arrives on the timetable: more than half a day, so not a connection we count.