Hello, 2 part question so wondering if anyone could shed some insights?

1. I am flying CX J from NRT into HKG, arriving after 10pm. I have my next flight also in CX J to TPE next morning at 8am. so roughly a 9 hr layover between landing and takeoff, and not really wanting to venture out of the airport. Any recommendations on which lounge(s) I could use? i'm OWE if that helps too

2. I have a travelling companion on the HKG to TPE flight next morning. Could he arrive at HKIA around the same time as NRT arrival, check in and join me in the lounge(s)? any complications on checking in late night the day before?

thanks!

Ah, my choice would be the Pier J. As an OWE, you have a roped off section to ensure there's space for you and it's still a very comfortable lounge where you could kill some time or take a shower until they close (assuming this is still the case) after the last flight departs at or around 1/2 past midnight? After closing, before the pandemic, there had been a 24 hour PP where you could bridge the gap until the CX lounges open again at around 4:30 - 5 am? When alone, I've done this many times and actually quite enjoyed the experience, and even have had a few interesting conversations with fellow overnight HKG pax.

In my experience, no. CX has never had issues with when my flight departs, even when it's the next day. I'm assuming as long as your friend has a OW BP, he/she will be able to join you in the lounge.

For a more comfortable experience book into the Regal airport hotel which is connected to the main airport concourse. If you have baggage the trolley can be pushed right into the hotel check in. Overnight room about HKD1000 (US135.00) at the moment
Decent 4 star hotel rate inc wi- fi.

When you go from T1 to gates 13-21, there is a new Sky Deck for plane spotting, you can spend some time there and get to know the airport expansion plan.
HKG has yet to return to its former glory and not many shops are in operation. I am not sure if there is any 24-hour option. On the other hand, in the terminal air-side area you will see some new games/booths for passengers to kill time waiting for their flight.
But the best option is still entering Hong Kong and get a proper hotel room. Regal airport hotel has provided me with bad service before so it is on my personal black list. But it should be a decent enough hotel.

I was advised in another thread some days ago that it would be simpler for us to transit without formally entering Hong Kong next week. We do have reservations at the Regal and an 18-hour layover in the midst of a grueling itinerary. Would you suggest that?

Oh, hadn't realized this and assumed some kind of shuttle had been required. In that case, with hopefully the return of e-channel, I'd probably opt for this, so long as I'm spared having to roam around looking for the shuttle stop.

Ah, probably would be "simpler" if only because some form of negative RAT wouldn't be required. However, since it appears these days HK will accept any indication of a negative test, not sure how much of a hindrance it really is in practice. Since the hotel is attached to the concourse, I'd probably go with this after an 18 hour flight.

If there is good reason not to enter Hong Kong (you can DM me for details if you wish), then probably you shouldn't rest at Regal. But 18 hours layover itself is quite tiring. So it really depends on why you shouldn't enter Hong Kong.

There is no reason anymore not to enter HK on transit, especially for 18h. There is no "risk" anymore, as you don't have arrival tests. As long as your final destination does not require a pre-departure test, it is hard to see why you would not enter HK and enjoy a rest at Regal or any other hotel. PLus some time in the city (but needs to wear mask).

Thank you both very much. Our only concern was if there were something we didn't know about requirements to formally enter Hong Kong. Transiting HND and SGN and eventually arriving at CGK on this itinerary kept us busy filling out online forms and downloading apps. We appreciate your reassurances and look forward to getting some rest at Regal.

At the present time, a RAT test 24hrs before departure to HK is still on the books. It can be self administered and one keep record of the -'ve result.
There are many reports that this is not checked by CX at check-in nor by HK authorities upon arrival. YMMV

This is correct, on my last entry neither checked, but better safe than sorry as a poster above stated it is still on the books and it is entirely possible they start to enforce it without notice. The website says record of the result should be kept 3 months,

Yes, you need to take a picture of a self-administered RAT test. Not a big worry.
Requirements at CGK might be a higher hurddle.

Since early this year, I have already made 4 trips from HK. Entering HK doesn't feel any different to pre-pandemic days - e-channels are open as normal (do check whether your passport qualifies), no covid-related checks administered, luggage delivery is normally quite fast. Last time my plane parked at the gate at 2220, and I made the Airport Express departing at 2245 with checked luggage!

In theory there meant to be random spot checks whether you have a photo of your RAT test, yet so far I have not heard anyone got checked or seen any such officer in the terminal, so my guess is that this is just a paper exercise and the requirement may be dropped quite soon anyway.

So yes I totally agree going to Regal for the night would be a better option - and up to you whether you want to retrieve your checked in luggage. At check-in at your origin, you can indicate whether you want the luggage checked through or want to get it out at HK, if you check through (I guess you don't really need the luggage for a quick overnight stay) then you don't need to worry about your luggage at HKG - you should be in Regal within 30 mins of disembarkation.

Airlines would check-through your bags if on an itinerary with transit, and normally not allow you to retrieve it.

IME, if the transit involves an overnight, most airlines would allow you to retrieve your bag.