Just when you think you've worked out how the ACO works, up pops another variation...
I did have the zoning letter in November time. And I also have my ticket confirmation letter, which doesn't mention zoning anywhere.
Having now bothered to read the glossy - all sites seem to have a 35m2 allocation except on Beasejour you can now get 105m2 for €150 (35m2 being €46), and a new site called Hunaudieres which is right on the inside corner of the entrance to the staight, where you only get 30m2, and can only use 2 man tents - but it looks absolutely trackside, and it has electricity! 
EDIT: Just catching up with other posts and I realised this is the one with erected tents with the logo discussed elsewhere.I wasn't aware that they allowed tents at Mulsanne and Arnage but there are prices for 35m2 at each of those too....
The extra night charge for MB is €15 pn, but I've never yet had to pay it...
And as they haven't charged me postage on my tickets, I guess I will just have to go down on test weekend to collect them...