Mystery solved ?

You will know her as Cyd.
I called her that (the female equivalent of Six Dinner Sid) over a year ago when she started to come into my garden. I resisted feeding her for ages but I was unsure whether or not she was a stray. I did resist giving her shelter in the house on one particularly horrid rainy night.
I'd asked around to try to find out if she was a stray. My brother insisted that she was too glossy, too well fed and without scars so she couldn't be a stray. It made sense.

Just over a week ago, all of us had a letter put through the door. There was a picture (looking like Cyd) and information.

She's really called Blu (oddly, so is my neighbour's little male cat who is also not blue)
She does have a home (no surprises there)
But she has a very sensitive tummy and food intolerances and they have her on a special diet.

So I've stopped feeding her.

She isn't happy - are you "Blu" :-(