And that highlights one glaring difference between how Covid policies are enacted in HK and Mainland China. In HK, quarantine hotels may be designated by the authorities but it's up to the poor old traveller to find availability and book one competitively through the hotel's booking channels... hence HK Bonvoy hotels awarded points and qualifying nights as usual. I cannot speak for the Sanya situation but my experience with a quarantine hotel entering the mainland (specifically the land border from HK in Shenzhen) was that you are billeted to an authority-managed quarantine facility that happens to be a hotel (in my case one of the Glorious Vienna Hotels) that have effectively subcontracted their facilities and rooms to the Greater Good and consequently there were numerous reports of Bonvoy members whose delight at finding themselves in a Bonvoy hotel for quarantine in some major Chinese city turned to abject distress when they discovered they wouldn't be getting points or nights.