That would be interesting, and I guess they need to keep it at f/1.2 because that sits it apart from competitors that don't offer any FF lenses with f/1.2 that has autofocus. I guess this is the merit of having a larger mount than Sony & Nikon.
However, I think the 135L needs to be upgraded with that BR optics thing. It's performance would probably beat Zeiss's 135s. I wouldn't be amazed if a new 85L gave Otus-like quality at half the price.
I better start saving!