My itinerary is a bit complex, it's Montreal-Pudong-Hong Kong-Vancouver?

Does Hong Kong count as a Chinese airport or a valid transit airport? I have business in both cities countries and my stay in Pudong is close to the 72 hour mark.

I'm Icelandic, so I'm valid for the 72 hour transit rule, I'm just not sure on the length of stay permitted and if Hong Kong is an invalid transit destination.

TORONTO SHANGHAI/PUDONG AIR CANADA JUL 29 1300 ARRIVE JUL 30 1515
SHANGHAI/PUDONG HONG KONG DRAGON AIR 02 AUG 15 1430 1705

And the question would become, do I need to transit elsewhere (ie Japan) then back to Hong Kong and apply for another 72 hour permit?

Thanks!