60 days M Visa

Hi, I have a multiple entry 60 days stay M type issued on on 30 Oct 2015, it also state "Enter before 30 Oct 2016". Let's say if I return to China on 27 Oct 2016, will I be allowed to remain there until 26 December 2016.
I just want to be sure and not be detained for overstaying. Thank you in advance.