Most likely right? Cause havent the prototpyes pretty much been the final product color? I can only think if Hound and Tracks at the moment.
Smokescreen proto was blue, Silverstreak proto was grey, Sideswipe proto was red. The only one so far to throw off the pattern is Dead End, who's proto was yellow. He may have been originally intended as Sunstreaker though, so that would explain the yellow. I would put money on Jazz/Meister being white.
I sure hope they'll keep this one white. It'd be even better if they run a blue stripe down the middle (i.e. Viper style). I didn't really care when they gave Tracks a yellow paint job. Let's hope they don't mess with Jazz/Meister.