As far as the spotting, my BRB has those spots on the side as well. There is a breeder currently trying to prove this out to be a leopard morph....i think. Also, BRBs are brown as babies, a lot of the wild BRBs stay brown yet keep the markings, while the columbian rainbow will stay brown/coppery yet lose most/all markings & just be a solid color other than a lighter belly.
I cant really tell how large it is, if its an adult, im saying BRB, if its young, could really be either, but im still going BRB due to the lighter sides and markings.
Shawn