FIV rescue cat desperate to go out

[KrustyTheKat]

I adopted my lovely cat 8 months ago from a rescue centre.
He is FIV positive so they insisted he needed a indoor only home.
I thought that’s great I live in a flat so he can’t go out anyway, it will all be ok.
So from day one he has shown an interest in getting out. He hangs around the front door and slipped out and briefly escaped one day.
Anyway, the last few months he’s been much worse, he constantly hangs around the front door meowing and he looks of the windows and claws at them like he wants out, he’s now jumping onto every high surface he can find looking for an escape.
I bought a harness to walk him, we’ve been out a few times but he’s really not too keen.
He was a stray before coming to me (probably not from birth but for a good period of time) so he’s used to his freedom.
I think he’s bored and feels trapped. I’ve bought him every toy I can think of, I’m home all day so he’s never alone but I feel really bad for him.
I’m seriously thinking he needs a home with a garden (probably secure so he can’t escape).
I really don’t want to give him up but I’m seriously concerned for his happiness and well being.
What should I do?

I also think he needs a home with a garden. There is really no reason why FIV cats need to be kept indoors. If neutered they aren't going to go around getting into fights and infecting the rest of the cat population. Some people say that FIV cats are more prone to infection/illnesses that they are likely to acquire by going outside. But most FIV cats live a long, happy and healthy life with no ill effects and going outside is going to make sod all difference either way. The rescue I'm with homes FIV cats to outdoor homes. I've had dozens of FIV cats living long, happy lives with outdoor access.

In this case I really think the rescue got it wrong. But what to do now?
He should be returned to the rescue for rehoming, but if that's their policy then the same will happen again.

@thecatneuterer I think your right. I think he should have been rehomed to a home with a garden.
It’s such a shame he’s a lovely, placid cat who likes a cuddle and a lap every now and then.
Where is your rescue centre?

London

@thecatneuterer I’ve pm’d you