Yup, I have been to Canada not do long ago and I still have a valid Temporary Resident Visa. The reason why I said I don't visa is because one needs only the letter of introduction from the Visa Officer if they are from a visa exempt nation (they need only ETA) or if they already hold TRV for duration more than the proposed period of study. Going by logic, My TRV is valid till 2025 and allows me to enter Canada whenever I want. So, All I need now is approval and a letter of introduction to show it in the border. However, other Indian students need TRV and the letter of introduction to Canada. So, I thought they might take lesser time to process my application but it doesn't seem like that.