Moondog,
thanks for your comments; I asked an agent in Hong Kong who told me I needed a visa just to be safe (and offered to get me one in 4 hours for $175) and a couple of agents in Sanya who insist that I don't. And, one also told me that the airlines know nothing about this, only the arrival airport officials in Sanya So, not sure how exciting checkin would be Agreed - neither the scenario of being denied boarding in HKIA nor being deported from Sanya (I guess you can't be deported if you don't get onto sovereign soil !) sounds palatable after paying for the tickets and hotel (even tho using PC 5K Point Breaks !)

ForeverCCA, what you say makes sense to me, as I believe it was the same thing that happened with transit visas - US citizens now require them except in PVG .......

thanks again; I guess we'll just go to Okinawa and save 20K UA miles