Controllers used the term ON sTandard.the pilot who heard non standard may have tried to get some sense out of the wording from his experience and got non standard as of an odd level flying west.
On standard means a FL so they want you to maintain the cleared 'altitude' on 1013.15/2992.
China Atc phraseology is very poor and they rarely listen to your readback so be very prudent.
For your info,the transition altitude in shenzhen is 2700m(8900ft)so if he clears you to 3300m(10800ft)you better be on standard.
Short briefing?
