BA 1349 then BA 464 at Heathrow
Saint Helier → London → Madrid
Timetable, London time
16:20BA 1349 from Saint Helier at the gate
13:45BA 464 to Madrid leaves the gate
21 h 25 apart on the timetable, overnight
BA 464 leaves 21 h 25 after BA 1349 arrives on the timetable: more than half a day, so not a connection we count.