+1(514) 937-9445 or Toll-free (Canada & US) +1 (888) 947-9445
I read somewhere in CIC sites that it is recommended to apply before 1st December for Jan intake for SPP category. But I guess a lot depends on the actual visa processing time for your country.
 
It can take 6-8 weeks. Depends where are you from.

http://www.cic.gc.ca/english/information/times/

Check processing times on official website and add 1 week to be safe.