I am not sure the 320 job at TIanjin will be very pleasant for a while. They are advertising for Capts and FO's and now expat mechanics. I don't believe they had any plans to get 320's as they have no pilots in the Chinese pipeline. They have no 320 pilots, and all the pilots going there will be trained by pilots at other carriers in the Hainan Group. That means Capitol Airlines. That means that short term you will be flying with Capitol crews (a good bunch of guys, except maybe me), but god knows where you will be flying. You might find yourself deadheading (for free) to a Capitol base and staying there all week. For months. Meanwhile we will be deadheading there to fly in Tianjin all week. For months. Staying in really bad hotels at the airport. Or it might work out fantastic and be a dream job, but it is a crap shoot at the moment. Once Tianjin Air gets your license, they "own" you in China. You can't work anywhere else. Choose your Chinese airline carefully as it will probably be your last as you can't just switch carriers.
I would hold out if you can. The Hainan Group, to which both Capitol and Tianjin belong, are shifting around 320 assets and people, much to the detriment of the people, both Chinese and expats. I think the plan is changing on a daily basis.
If you can screen, and then hold them off for 3-6 months, that may not be a bad idea. Right now it is a goat rope, and we are living it.
It might turn out great, or be the worst nightmare you ever lived. And you will have no say in the matter other than resigning, which is my choice currently. We are doing this exact same thing with another Hainan Carrier, Lucky Air, for the exact same reason, and having been doing it for 3 months. We are about to start the same circus with Tianjin Air.
Capitol is the only 320 operator I would recommend to someone in China, but at the moment I wouldn't recommend them. Tianjin Airlines I know nothing about other than they are a sister carrier in the Hainan Group, and they had no plans in place for 320's, and no 320 pilots other than "wet leased" ones from another Hainan carrier. Us. The instructors here are all great guys, but they are very senior. They are not going to commute to you, you are going to commute to them. That means lots of dirty hotel time in Xian and Beijing, and if you are lucky sometimes, Sanya. And I believe most Hainan group carriers do 300 hours of line training.