What's the process to transfer to the visa?

Shawn, if you plan to quit, you should get the release letter from your current employer. Then you should have your employment certificate/foreign expert certificate cancelled. Your new employer is responsible for getting your the new employment certificate. Finally, you go to local entry and exit management bureau to apply for the long-term resident permit. It's possible that the bureau might ask you get back to your country to apply for a new Z type first and then return to change your Z into resident permit.