I've done that kind of ukemi, just for fun - for me it's a completely normal forward roll. Just starting the wrong way around
Actually, I dont think you could (/should) substitute that for ushiro ukemi in most of the techniques. It mostly feels to me like turning out of the throw and losing contact... (but then I don't like forward rolls from tenchi nage/sukkumen iriminage etc. for exactly that reason and I'm aware that a lot of people like doing them).
Anyway, it's definitely not a new version of ushiro ukemi, if anything, it's a version of mae ukemi.