Salam Dear,
After submission of your application to CPC - Mississauga upon your approval letter for the stage one you get a letter that your application transfer to CHC - ISL but actually instead it goes to CPPO - Ottawa and give and take stays there for about 10 to 12 months collecting Dirt and dust ( I have heard sometime they use his papers to Eat Bolani or Pakoras or Shawarma it depends on immigration officer mode . ) after that whatever left over they scan and upload it to what they call E - storage server to be available for immigration officer review in CHC- ISL. once your case get transfer to Islamabad they will do the initial review there to see what is missing documents need to be provided and what is expired which is the Medical and Police Certificate ( They are only good for one year from the date of issue ) so if its passed they will send you to re do it. now once case gets to CHC - ISB it all depends if mailing address or contact info is correct so there is no delay on correspondence and if all documents right and straight forward your case will be in and out about 6 month average + CPPO - Ottawa timing, so all together around 16 to 18 month, if there is a delay for example strike, holidays, or complex cases that required more background checks mostly Husband cases specially if there is ( Military service or Govt Service involved or verification or investigation) it will take longer 20 to 24 months extreme complex cases over 30 month. Keep that in mind that CHC - ISL runs 2 background checks for husbands one before Passport request and one after once passport received , wife cases only once. so dear that is the processing reality in nutshell for Afghan and Pak nationals. you will see some exceptions once in a while that some is 12 or 14 months but one or two case does not count the majority is above I mention. hope this info help you understand the reality and prep you mentally to deal with it. in my case is about 25 month now from submission its all done and I am still waiting for Passport request for my wife, see what happens. wish you all the best.
Regards.
CVimm