Yes, there IS an age limit in China with respect to the issuance of Z visas.
Teachers aged 65 and over are no longer issued Z visas.
Jay Gee

Sorry, Jay Gee, one might hope that things in China were as black and white as you seem to imagine. However, that's definitely not the case. If all schools that hire foreign teachers followed the guidelines to the letter, there would be far fewer FTs in China than there are, and I'm not just referring to age limits. I'm also referring to degrees and etc. FAOs and PSBs have the option of interpreting rules and regs in whatever way they see fit.