In all seriousness, there is not. I view the lack of transparency and consistency in processing upgrades as a serious failure on the part of Air Canada.

For me, the worst is the "gate wait" where you have no idea whether to board first (in order to secure overhead bin space) or to hang around at the gate to see if your upgrade clears. You can try to ask but I find it stressful and inconsistent.

Another issue for me (which I accept is not directly related to your question) is the fact that the system will not offer an LMU for purchase at check-in where you're on the upgrade waitlist. If I can see the flight is full-ish I'd like the option of being able to decide which "currency" to use, cash or eUps.