Thanks for your suggestion. The 6:30 flight via Toronto is just too early with a toddler so we decided to go with a 7:50 departure, connecting in Denver.
Of course Air Canada didn't offer any sort of upgrade,compensation or explanation why they didn't even bother to notify us of the flight change. When they emailed the new itinerary I had to laugh at their 2 1/2 pages of "conditions of contract". Too bad we the passengers don't seem to have nearly as many rights. I'm tired of being jerked around by their aeroplan system and now with flight times. They've just lost our future business. Grrr!!!