I came to Canada with expired PR card in early Aug 2016 via US border and I was waved at that time. I did not go out and just completed 2 years a couple months ago. I am going to submit PR card renewal since I need to travel to visit my grandma overseas. I am a full time university student, just completed my second year. How to prove my 730+days staying in Canada. Is the letter from my university stating I am a third year student will be sufficient? Thank you.