Hi. I realise that this conversation began a few weeks ago, so you may have moved already. If not here are some things I've did with my 10 yr old with ADHD who exhibited/s aggressive behaviour as your son does.
When we moved I gained as much information about the place we were moving to - photos of the house, particularly the room she would be going into. So that she could see and be prepared for what we were moving to. We also discussed what we could do with the room immediately when we arrived, for eg, posters she could put up. We had a box which traveled with us containing things she could set up in her room immediately - sheets, posters, toys etc. Make sure you have the equipment ready to put this stuff up. We used the command sticky tabs which come off without destroying the wall.
You may also want to find out information about the community surroundings - school, playground, shopping centre nearby.
Obviously all this takes time and I realise you're extremely busy already.
The other thing I did which has helped change my daughter's behaviour dramatically is to cook her breakfast every morning. She has an enormous breakfast usually consisting of eggs and I try and throw some salmon in there too. She will also have a smoothy consisting of banana, spinach, ground flaxseed as well as berries.
The website that has really helped change establish new eating habits was www.ourfamilyeats.com.
The other thing that really helps when she becomes stressed, is for her to listen to a talking book with head phones on. She really enjoys it and it takes her out of her stressful life and allows her to escape for awhile. If this may work for your son, just make sure you set up definite times when he can't listen, getting ready for school, dinner time etc.