Hi, Jasper has come back. On advice from the Cats Protection League he’ll be kept in for a week or two. That should get him his bearings back, relearn where his real home is, and forget about whoever’s been trying to keep him.
Please keep an eye out for people feeding or housing cats. It’s cruel, and the cat is the legal property of the owner. If you know of anyone keeping cats without the owner’s permission, they could be charged with theft.
Whilst it’s always better to resolve these issues face to face, owners go through hell worrying about what’s happened to their pet. I would totally understand any owner pressing charges.