CC is correct of course. It's absolutely possible.

However, OP, your scheme falls apart because of the number of eUp requests filed by the huddled masses in the back of a tripple seven YVR to YYZ. Those will all clear first, and there will be a lot of them.

I'd practice the technique on your short haul flights and sacrifice the credits on this one.

If you risk it, let us know how it goes.