[Piebald]

I'm sorry Dr Mck, was he an entire male? They do wander unfortunately. However, I'd suggest looking for him. I had a feral out door cat who would get stuck in garden sheds. I had another, in the States, who would get locked in garages. Ever curious they go places and being feral, are too afraid to ask to get out. Put out some notices in the neighbourhood and maybe knock on a few doors. I've done all this and-- I would send the neighbourhood kids out to check sheds. My success rate is 100 percent, touch wood, but all my cats were fixed (trapped and released when necessary). Good luck, I am sorry and hope he comes back.
That's great the others are starting to come in. xx