I've listened to an interview with a Canadian Embassy officer in Turkey recently (and she pointed out that Embassy permitted her to give this interview), she clearly stated that they will start issuing PPRs once the international ban is lifted.They won’t. The vaccine requirement will always be there as long as there is Covid in the world. 7 September will be when anyone travel to Canada for any reason. There will be no “exemption” list to check against.
If still after that date they continue to hold PPRs then they just don’t want the outland immigrants in their country.
I don’t see any reason why they would do that though.