He was last seen at 9:00 am in Vancouver, but the actual time he would have left Vancouver to arrive approx. an hour later and be seen at Delaney's on Lynn Valley Rd is unknown. Sunset was at 4:20 pm that day, so I can't see him choosing the lengthier trails that would have kept him out past sunset.
I don't think people fully understand how early the winter sun sets in Canada, so a British tourist may have assumed, without thinking it through, that he had until 8 PM. If he was caught off guard by the setting sun, he may have tried to short cut his route, and found himself in trouble.