Following in the footsteps of the US versions, the Galaxy S8 and S8+ in Canada are now in the process of being updated to Android 8.0 Oreo and Samsung Experience 9.0. It's definitely been a long time coming, but the update is finally rolling out.
So far devices sold by Koodo, Rogers, Videotron, Bell, Telus, Virgin Mobile, Fido, and Freedom Mobile have received the update notification. You should also get it if you bought your handset unlocked. Note that you may need to manually check for the update through Settings in order to get it.
The build number for the new release ends in BRB7, and it's a 1.3GB download so you're probably going to want to download it on Wi-Fi.