The Pro has a wide range of adjustment, so in a pinch you could run darn near any fuel mix.
A week or so ago I was on the way home from Norwalk, and was down to 1/4 tank of E85 or so (I am currently running E85). After checking 2 stations, and giving up, I put 10 gallons of 93 in the tank, pulled 10% out with the "Mainscale" setting in the Pro, and drove home (2 hours or so). Ran great, no issues.
Bob