Before I left at the end of my contract, I tried to get a no accident letter and a no criminal record letter. The airline I worked for was based in PEK. I was based in a different city/province. I applied to the PSB (Public Security Bureau) in my province. They told me my company is in PEK, and my work visa was issued in PEK. I have to do it in PEK. I tried at the PSB in PEK, they said I cannot get one as I don't live in PEK. So no No Criminal Record Letter.
I asked my company about getting the CAAC to make a no Accident letter. They said "sorry we don't do that".
If you are a career contract pilot, working in China might make it difficult to get another contract job.