YUL-GVA is operating on a A330 this summer so this is a significant increase in J seats available on what used to be operated on an B767. The one thing to watch for with this flight is that it actually operates as YYZ-YUL-GVA and my recollection is that for airport upgrades, AC may decide to allocate a certain number of seats for people departing from YYZ all the way to GVA and then reserve some upgrade space for those boarding from YUL.
YUL-BRU also appears to operate on a A330 this summer and does not have the "drawback" of being a direct, one-stop service from YYZ