People who have already paid their fees will get a refund.
Concerning the process, I'm just trying to recall. I think what we were doing was that people who are in Canada would receive a letter, if I recall correctly. If you've paid your fee but not landed, when you come to the port of entry you will receive a form, and you can apply for your refund. And if you applied within Canada, then you will be sent a refund directly.