The length of the canola season really depends on the germination. If the plants mostly germinate at about the same time, season is is some 4 weeks. If germination is uneven, as can happen in a dry spring, and then there is some rains, the season can be 8-10 weeks. There does need to be some moisture in the ground to get a good nectar flow and longer flowering period.
Canola honey does crystalize in the comb, so need to pull supers and extract every couple of weeks. With a strong colony, bees will make a 100lbs of honey in a week. Canola honey does not have much taste, It has a taste much like sugar. Consequently, it is good for baking. It also can be blended with strong tasting honey, if you desire to cut back the strong taste.