I'm not sure what you are complaining about - it is the law - your work permit Z visa is linked to the employer who sponsored you to get in the country - if you change employers it is automatically void, cancelled and you have to get a new one from your new employer. People who do the wrong thing make it difficult for the rest of us living and working in China.

After you enter the country using your Z Visa, it gets canceled anyway within about thirty days, and it's replaced by your R-permit, and by law your employer must hand over to you your Expert's Certificate. At that stage the employer is usually the first one to break the law and upset the FT,,because normally the employer will not give you that certificate, it remains in a cupboard unsigned (Ft is supposed to enter his/her signature in the booklet, it's the law)

Before arriving at your new school the employer will at least show you a sample degree. It's often total nonsense, and at best they tell you lies by omission, regarding your flat, wages or working conditions. Now, very knowledgeable person, it takes two to tango, and if the situation at your new school is not how you were promised you should have the right to terminate your contract when it all gets too much for you.

On the contrary, it's the FT's who allow bad Chinese employers to ignore the promises they've made, or not inform you it snows inside your classroom that has made life very difficult for other FT's in China. They have started to believe we are all soft in the head.