Hi there, no worries at all!
The campsite is actually owned by Yelloh and Keycamp and Eurocamp are basically holiday operators using the campsite. There are several other (foreign) operators on site too as well as the Yelloh brand. The Keycamp and Eurocamp mobiles are located towards the rear of the site, which is good because you are some distance away from the bar, resturant and theatre area, where you can get a fair amount of noise, but its always quiet by about 11.30 - 12.15am. anyway.
In terms of rules it is therefore Yelloh who impose them, which to be honest its more about etiquette than rules. They do have a trunks only rule for the swimming pool. We all tried to ignore it for a day or two but eventually got asked to change. My 17 year old son said exactly the same 'over my dead body will i wear trunks' but to be honest, everyone wears them and if in shorts look more like the odd one out. They sell the trunks, which are more like black stretch boxers, not the old speedo type at the campsite shop but are quite expensive so best take your own. I put money on it that your boys will relent because the pool complex it so good, plus they can join in the water polo and pool games.
The site closes the main gates at about 10.30 and have security guards on throughout the night which is quite reassurring.
If your going through Keycamp or Eurocamp then your kids will be able to join in with Fun Station or Base, all of ours did, and Base went down really well with my older two, they did go karting, surfing, high wire, beach party etc etc
The kids stuff took me a little by surprise, they all met friends and really didn't want to drift far from the site which can be a little frustrating when you say to the kids that tomorrow we'll have a family day out, becasue all they want to do is the activities, which is not a bad think but just worth considering becasue the morning session is 10.30 -12.30 and afternoon session 4.00 - 6.00, so you end up trying to arrange things around those times. By about the second week, we had it sussed!!
Hope this helps!!
We've booked again for next year until the end of July, if you are there between 30th July - 3rd August, make sure you make the Bayonne Festival, we missed it this year but will be going next, its supposed to be fantastic, bull running the lot!!!!!!
Regards