Update! There was a dog on the M20. When I got home I got a whatsapp from the kennel mum where I had been in the morning, and go twice a week to feed the dogs, to say the dog was OURS! It's a small lurcher recently on arrived from the dog wardens up in North Kent. She's a stray and very frightened. I sat with her on Monday to calm her down and she went from a heart beat at almost constant to much calmer sitting on my lap. So much so that when I took my hands away she stayed there. Unfortunately, she bit through one of the window safety cords and escaped. She found her way about half a mile to the M20. Luckily, traffic stopped and the police cornered her and took her back to the foster.