The original bid said that 7 group matches, 2 round of 32 and one round of 16 match would take place in both Canada and Mexico, but I think the current format is up in the air since FIFA has changed format from sixteen groups of 3 to twelve groups of 4.

So BMO could still be on the hook for a later round of 32 or round of 16 match in addition to the first round ones.