According to my recent experience with XA, you can not trust them.
I was invited for assessment in March, I did a lot of work to get ready like studying for the ATP exam, doing pre medicals, getting a Visa, arranging time off and travel reservations.
A week before going to Xiamen, they sent me an email saying that they realized I was too old. i will be 55 at the end of this year.
I tried to discuss this issue with them but they didnt wanted. Decision was final.
it seems that these Chinese airlines are like nazis. I hate them.