Quote Originally Posted by Sinnertwin View Post
If numbers were determined by character, then all of the new Seekers would have their own, along with the likes of Loud Pedal. Even the little red corvette Road Rage gets her own number. Poor Loud Pedal on the other hand just gets an L.
Seems to me that they're just numbering on the fly.
I think the best theory is mass release toys get their own number, limited releases or exclusives like Loud Pedal do not.

Having a quick look at the list, it seems to fit well with the numbering history