It's like Deja Vu when this comes up. I put it in the same category as the chin cup. This could be the collar, the balaclava, a combination, etc. There's just not enough on-screen, visible, clear evidence to support them. However, we all know "stunt" versions have modifications that "hero" version do not necessarily have...and vice versa.
Perhaps when the SW costume book is released we'll all know for sure. Perhaps not. Until then, we dig for more evidence and truth as Chef mentions. It's part of SW costuming fun!