Welcome China Pig (I'm from South Glam. but living in Hampshire)
Thank you Celyn. Get back to Wales immediately!
It depends how long he has been feral, how old he is and what has happened to him in the past. If he has ingrained distrust of humans, it will take time.
I live out in the country with few neighbours, but a family living not too far away may be the cause of his problems. You know the type: garden full of cars in various states of disrepair, loud music at all hours, similarly the shouting, police visits regularly, etc. They also own a rotweiller! I think our stray may have been one of their cast-offs.
For the moment do you have a shed that you could place food, and a bed, inside, so that he can get used to going into a restricted space that is warm and dry. Cats are canny creatures and he will be finding some where warm and dry to sleep.
Unlocked sheds are too vulnerable these days, unfortunately, but he seems so healthy now that I'm sure he has a safe place to sleep - probably a warm farm outbuilding.
I'll keep feeding him through the cold times and hope for the best.
Don