Not sure.

Have you checked the available dates over the other consulates ? Maybe you can double check your reservation online to see if there is a typo in date.

I'm not sure about the changes in Vancouver. If this is what you see from the confirmation letter, probably it's different now. If you think 3 days is too long to wait, maybe you can check the other consulates to see if they have changed the policy. I don't have the info you need at this time. By the way, Vancouver is a good city for touring why don't you consider that. You have had successful experience in Canada before should be no problem this time.