@chillminx, in answer to your questions -
The food situation - he was back on Whiskas, then the vets sold her pouches of Purina food for his stomach last week which she used up until going to the vets yesterday. They've now given sold her the Hills food to give him permanently which the vet says his cats eat and do well on but as soon as she got him home, she gave him a tin of Thrive :Banghead. I'm having trouble getting through to her the need to introduce food gradually and not keep changing. I believe she gives him four meals a day which I did tell her to cut down to three as I thought this would be overloading his tum. I have been thinking that perhaps 5-6 smaller meals would be better as he is so obsessed which gives him less time to get frustrated between meals.
I think she's given him one meal of cooked chicken but that's all.
He has his last meal around 8.30 then nothing until the morning. Once he has settled down for the night he isn't any trouble.
It isn't specifically around mealtimes, in fact, it's at its worst in the evenings when he voluntarily sits on her lap while she watches TV. She does pet him though she says she knows not to do it too much. She was kissing his head which I told her to stop as that could be pretty dangerous if he suddenly decided to lash out. She said sometimes she doesn't have to be doing anything at all and he does it. I do wonder myself if its frustration of wanting food but not getting it.
He lashes out occasionally at her feet when he is just lying down on the floor and she passes him to go to the kitchen. One positive is he does seem to have learnt that he can't just go into the kitchen and jump up on work surfaces trying to find food which he did repeatedly when he came.
@Cully, I totally agree that it will take time for his brain to adjust to knowing he will get regular meals, you can't switch off 12 years of possible neglect in five minutes. Toppy was much the same when he came always wanting to be fed.
I don't think Orlando's ever done the full wrap around your arm thing like Misty, its just quick one off bites or scratches. The kickeroo or teddy sounds a good idea to deflect his aggression thank you, I'll suggest it.
I am really hoping given time he will improve, its only been three weeks after all, but I'm not sure she can put up with it much longer. It's such a shame as in all other respects he's a lovely cat, he just has a Jekyll and Hyde personality.
I'm a little annoyed that the vet has suggested to her he is not the cat for her which could be influencing her thinking. She was very lucky with Charlie that he was such an easy going boy but all cats can't be the same anymore than people. I don't believe in giving them back the minute there's a problem, you do have to work at it and usually love and TLC will reward you. She isn't a very experienced cat owner, before Charlie she hadn't had a cat for a very long time, so she doesn't know how to deal with problems.
I haven't been in touch yet today so we'll see how things have been since he came back from the vets. He was a little spaced out last night.