http://www.cic.gc.ca/english/information/times/canada/cit-pr...
http://www.cic.gc.ca/english/information/times/canada/cit-pr...
What this means is that in theory, someone could land as a PR one Day 1, file the application exactly 3 years and 1 day later, and then leave Canada and go sit in a hut in Guatemala while the application is being processed. [1] After it is ready for the test/oath in 2-3 years, applicant flies back, declares a desire to live and die in Guatemala, and still gets his Canadian citizenship, a shiny new Canadian passport, and leaves the country. And all this is 100% legal, at least as per Canadian Citizenship Law as of 2013.
[1] Unfortunately, C&IC will only correspond to Canadian addresses, so the applicant does need a reliable mailing address in Canada
There is ambiguity about whether it's a rolling 5 years or whether it's 5 year cycles based on the date you first receive your PR status. To be safe, it's usually best to assume modulo 5 from the start of your PR status.
In the example above, if you filed the citizenship application 3 years and 1 day later, the maximum you can stay in your Guatemalan hut is just shy of 2 years, or else you risk losing PR status and jeopardizing your Canadian citizenship application.
[1] http://www.cic.gc.ca/english/newcomers/about-pr.asp#keep_sta...
(Having no dog in this hunt as I'm not Canadian nor do I have any claim on Canadian citizenship or permanent residence, much as I'd like to.)
Good discussion here: https://secure.immigration.ca/forum/forum_posts.asp?TID=8848... (see a post by dpenabill toward the end of the page), and the entire thread is good as well.
The estimate is based on "processing time from receipt of application to final decision for 80% of cases".
The rather excellent British Expats (not just for Brits!) forum users keep track of the various processing times of Canadian immigration applications.
http://britishexpats.com/forum/forumdisplay.php?f=33
British Expats forums is a great resource for anyone trying to move within the English speaking world.
I got my citizenship about ten years ago (I only know because I'm on my third passport), about six months after applying and taking the test. I had been resident for just under four years at the time.