How long in the Pier and/or Wing?
 

I am arriving HK at 6:30am. My hotel won't let me check in until 2pm. How long can I stay in the Pier/Wing before they make me leave? I depart HK at 12:05am, but I must check out from the hotel at noon. When is the earliest they will let me in one of the clubs? What are their hours open?

They are departure lounges. You need to have an onward BP to get to the departure level. You may be admitted into the CX lounges based on your status and your onward flight.

Unless you're in transit, I don't think you'll be able to get to either of the CX lounge complexes on arrival. At HKG, you deplane "downstairs" and are funneled straight through to Immigration at the main terminal. To get to the lounges, you have to go upstairs first (then back down!), and to get upstairs, you have to go through an intermediate security screen, where they want your same-day onward ticket and boarding pass. No ticky, no pass.

But I'll bet you can get an early check-in at your hotel.

And on departure, you can come as early as you wish -- the lounges are open throughout.

Well, not exactly. The main lounges open at 5:45-6:00am. Before that only the mini-Wing is open. I would suggest not to get there before 6am.