Aren't the those type of plates dealership plates?
Yeah, at one time. Now the newly issued ones are white background with red lettering. But if they haven't turned them in, motorcycle dealers may still have those blue background plates with white lettering that they can throw on their fleet and demo bikes.
This thread had a good summary:
I did a little research.
At one time in Ontario, motorcycle dealer plates were blue with white numbers.
They have been up-dated to white with red numbers, but if you still have the blue plates, they can be renewed.
Car dealer plates were orange with black numbers, but these have been replaced with white with red numbers.
The orange plates can continue to be used but the MOT is trying to phase them out.
An old timer was telling me about motorcycle plates from the 1960s. They had 3 plates in those days.
One on the back and one on either side of the front wheel.
You would get your new plates in April because then you would only have to pay for three-quarters of the year.