Having been to a meeting in Peterborough, I fired up the Trackomatic which suggested he was in Chatteris, so headed over that way. A bit of guess work and a spot of luck meant I saw him near Somersham. Span the motor round, overtook him and parked up for some photos. Yelled some encouragement at which our hero raised his head. I was slightly surprised to see what a gentle pace he was doing. The Android app still thinks he's in Chatteris. I'll post the pics up later.