Fwiw...

We were in HKG recently and on our way through security we were stopped and told our carry-on was unacceptable and would have to be checked. This was the same luggage we had arrived with and had done much travel with in the previous weeks (on UA). Despite our objections, we were not allowed through to security without going back to the UA counter for an 'Exception' pass for our bags. The UA agent was neither surprised nor approving of the fact that we had been refused entry and simply stuck tags on our bags.

I tell you this so that you might save yourself some time and aggravation by getting one of these 'Exception' passes before trying to proceed to security. Considering you will probably be cutting your time close, you wouldn't want to have to dash back for something so trivial (and probably unnecessary).

Hkg was fantastic - enjoy your time there!

DD