BA 425 then BA 1356 at Heathrow
Málaga → London → Saint Helier
Timetable, London time
19:50BA 425 from Málaga at the gate
19:00BA 1356 to Saint Helier leaves the gate
23 h 10 apart on the timetable, overnight
BA 1356 leaves 23 h 10 after BA 425 arrives on the timetable: more than half a day, so not a connection we count.