They are relying on franchisees for the expansion. This will be a tough ask, given the market dominance of Tim Hortons, and the continuing expansion of Starbucks . And, there are other competitors like Second Cup and Robins, as well as a number of independents.
Prospective franchisees will require sizeable balls and a capacity to withstand at least initial disappointment while they wait for their stores to become profitable. I predict the roll-out of Dunkin' across Canada will be pretty slow.
Having said this however, the Dunkin Donut stores that used to exist in Moncton when I first moved here were popular. It will be interesting to see what happens.