Back on topic, finally. Less than two weeks ago I jumpseated on a Hainan Air 330 flow by an expat. After we landed in SYX I asked him about what kind of schedules the expats were getting. He said in the past year they do almost exclusively domestic. He said over a year ago they used to get a decent amount of international.
The 330 does do some decent domestic trips. He was doing a PEK-SYX-PEK. Almost 745 hours flight time for a one day trip and he gets to sleep in his own bed that night.
I haven't heard anything more about the 330 CCQ and I have asked a couple of 737 guys at Hainan. They didn't know.