Definitely not true!
There might be discussions about the interpretation of the contract.
I finished my flying career and have no need to sweettalk any deal but concerning my three years with Hainan I treated them fairly and got the same in return. I might have had the advantage of beeing employed by another chines airline before Hainan so I was already used to the logic of the chinese mind.
No regrets about my last three years. There are better contracts out there but definitely worse. And I got my salary and bonus always on time.
Good luck