AC 864 then BA 1346 at Heathrow
Montréal → London → Saint Helier
Timetable, London time
07:10AC 864 from Montréal at the gate
06:15BA 1346 to Saint Helier leaves the gate
23 h 05 apart on the timetable, overnight
BA 1346 leaves 23 h 05 after AC 864 arrives on the timetable: more than half a day, so not a connection we count.