Congratulations! So happy for you ; )
I am also HK visa office. How long was your background check?
I only noticed it saying "background check in progress" a few days before they asked for my passport. I probably hadn't checked in a few weeks though, so who knows. Oddly, it still says that, and also says other stuff like "we are reviewing whether you meet eligibility requirements", but when I log into the other system, under "permanent resident status" it says "decision made". I think the other system is more up to date.
Rough timeline: Application received - August 27th, Acknowledgment of Receipt (Sydney) - December 5, Medical Asked for and Completed: December 20 - 27, Acknowledgment of Receipt (Hong Kong) - January 30, Ask for my passport - a week ago.
Hong Kong also sent me an email in the middle that seemed to be generic asking for a bunch of documents I had already sent, but the specification were a little different from what I had sent, so I resent those documents.
The only thing that worries me now is that I have a Canadian mailing address in the system, and my home address is the correct one where I live in China. Hopefully they mail the passport back to the home address, not the mailing address.
So many different worries going through this process, so much time spent. Nice to be finally over. Good luck everyone!