From what I have read on camping sites, it can be any 28 days in a year, not consecutive, for you to need no planning permission for up to 5 'units'. Apparently going via a club allows them to licence it in some way and they also advertise, but we'd prefer not to have groups, we don't want to aggravate the neighbour, or cause noise issues for ourselves. You are advised to check with your local authority, but I can't get them to reply to me and given that one neighbour has been illegally developing his agricutural land for years with no action taken against him, I am guessing they don't have the time to worry about these things! All the same, I don;t want to give any mendacious neighbours (as if there could be such a thing, in the lovely countryside, ahem) ammunition, I want to be strictly legal.