I was going to ask if she had any lower-lip markings but Sabinos normally have white flecking around the flank and barrel. Her back-end roaning lead me to think she might have a higher possible chance of being a roan. (Which technically you could still "call" her a Red Roan Tobiano though it wouldn't be geneticly).
Another characteristic is white "frosting" at the dock of her tail where alot of white hairs make a sort-of scruffy line near the top of her tail although that is with the Rabacino pattern.

Now I'm interested to know which she is!