While anything is possible, I find that most situations are best approached by maximizing for the desired outcome. As such, take the following for what it's work and good luck to you:

YC has a clear and openly stated bias for founding teams of 2<=X<=4 entrepreneurs.

Traction trumps MVP any day of the week. If people are already using your MVP, stress that. Traction is a commonly used de-selector.

The investor preference in SV is such that (it's likely) one of the first things required for a seed round will be some sort of DE or DE & CA incorporation. Since YC companies get funding, it's likely they'll require you to do the same. This is probably an area that if you choose not to give on where the company is incorporated, you'll turn off a lot of investors from SV. If it's a deal breaker for you, seek Canadian investment.

-Best of luck