It says nothing about booking in caravans on the info sent by the club in the BRCA pack, however we ran a regional there last month and it was so wet we had to get a jeep to tow the caravans back up the slope onto the pitch as it was that wet.
So if you are going with a caravan, bring a tow rope and a 4x4.
Oh, and can you tow me out when i get stuck!