HI Peter,
I have heard the same thing. Geoff Bryant would be the one to ask.
I am pretty sure this would not be a cams requirement. Cams do not require any form of roll over protection and a standard lap sash belt is fine, for road registered cars running at club level sprints.
Don't quote me on this but I think they are looking at making sure that roll bars are "true" and that an approved harness is used.
I think there are not to many cars going that quick that would not comply already.
I think it is a good thing to lift the requirements.
While we are at it, I think we should also ban the use of "race thongs"
Phil