Producer Mark Lysakowski posted this yesterday -
https://instagram.com/p/7ONteptRYv/"Well today is the day. #theamazingcrew #theamazingracecanada post production team picture locked the season 3 finale. Now it's off to the online to get it all pretty and perfect for everyone to watch September 23 on @ctv_television but don't forget we still have more race coming your way next Wednesday at 9 PM - when the racers come back home to Canada and land in @hellobc Until then have a great long weekend. @amazingracecda"
So they're not pushing it ahead to Sunday like last season
That's just 2 days before the US premiere.