Theddlethorpe, Huttoft, and Mogg’s Eye are all large, sandy, very quiet beaches in Lincs., and all are designated by the authorities as being open to dogs all year round. We adhere to the same standards on those beaches as we would in an open field - we pick our dog’s shit up and dispose of it properly, we take steps to control him as and when we find ourselves approaching other people/dogs, if their dogs and ours react well to each other (it’s unusual for them not to) we let them have freedom to interact, socialise, and play - never had any kind of problem in ten years.