I think you need to spend 730 days out of five years to keep your
PR renewal (for lack of word). The clock starts from the day you do landing as a
PR.
Please confirm this with a qualified immigration Attorney or on the CIC website.
I understand that the current situation in Canada is no longer favorable to get
PR or even work permit. Why don't you stay for two more years and get CDN Citizenship? I am sure you must have a strong reason NOT to do that.
With EB3 solution nowhere in sight, I am moving due to concern about my growing kids and their education. I have already delayed my move for two years but now my time is running out.
Good luck!
Bhattji