BA 423 then BA 574 at Heathrow
Málaga → London → Milan Linate
Timetable, London time
15:00BA 423 from Málaga at the gate
14:50BA 574 to Milan Linate leaves the gate
23 h 50 apart on the timetable, overnight
BA 574 leaves 23 h 50 after BA 423 arrives on the timetable: more than half a day, so not a connection we count.