AC 1803 then AC 854 at Toronto Pearson
Kingston → Toronto → London Heathrow
Timetable, Toronto time
20:25AC 1803 from Kingston at the gate
18:05AC 854 to London Heathrow leaves the gate
21 h 40 apart on the timetable, overnight
AC 854 leaves 21 h 40 after AC 1803 arrives on the timetable: more than half a day, so not a connection we count.