Well, someone ate the food delicately yesterday evening after I had logged off here and it wasnt Blip as she was in with me. I put some more out and it wasnt eaten last night but it has been eaten during the day (of course, that could be any local cat). I have replenished the bowl and water.
I rang our vet surgery and no such cat has been reported missing to them. I have checked the local lamp-posts and the only missing cat is an all-black six-month old called Dusty: I shall keep a look out for him
I have checked all the usual Internet sites and there isnt a cat fitting the right description.
We just have to keep trying and I shall update on any progress. The mews is a bit of a draw for strays, plus there are several "mad cat ladies"* round here so if he is lost, he will probably stay in the area.
*as for me, that is a destiny, not a description.