EI 158 then BA 1348 at Heathrow
Dublin → London → Saint Helier
Timetable, London time
11:25EI 158 from Dublin at the gate
08:35BA 1348 to Saint Helier leaves the gate
21 h 10 apart on the timetable, overnight
BA 1348 leaves 21 h 10 after EI 158 arrives on the timetable: more than half a day, so not a connection we count.