Sounds like DD2, who is emotionally immature, attachment difficulties and complex PTSD!
However, she was moving from special primary to a special secondary. They were great with pre visits, listening to me etc. They knew me well since DD1 went there as well!
I think what will make a huge difference is how well school understand and are willing to accomodate him given his attachment difficulties. If they are willing to learn about it and take it board it will be a lot easier. If they aren't helpful with dealing with difficult topics, or understanding his way of doing things, it will be a lot harder
He might well have problems moving up the school if he remains immature whilst his mates do mature. I know the gap between DD2 and her peers hasn't become any less pronounced as she ages. If he's easil led and impulsive it will become a problem if his mates decide to do something stupid. The other thing I find is, my daughter will find friends for herself that have problems like her - don't know how she does it, she just knows who they are!! She was in mainstream primary when she came to me, and within a week and a half, she was a fully fledged member of the troublemakers group!!
A majority of the adopters with teen kids i know have had secondary school problems - though not all. Mostly either problems with work, and the school not really doing anything, or struggling in the environment, or with their friends
I'm sorry I don't think I'm much help. Giving him pre visits sounds very good, seems so far like the school are happy to help
The only other pitfalls i can think of now are - what will he be telling his friends about himself? Is he very private or does he tell strangers the intimate details of his life story?! How are you going to handle facebook? Since it's a great ground for bullies as well as best friends! Harder to get them online as well, since you can't prove they did it! Those are things I have dealt with in the last couple of years
Hope that's a bit helpful
Lilka xx