8year old recently diagnosed.... hates school

My son has been diagnosed with autism, he has always struggled with school and the reason he says is due to being away from me and home. The school have put someone on the gate to help welcome him in but I get the usual ‘he’s fine after a little while’. They are trying to help but it’s very frustrating going through all the emotions and anger at home and having that sinking feeling that he is just coping at school and not truly being understood. 
I am in in East Sussex and was just wondering if there is any local people on here who can point me in right direction of support?

do people use visual cards, have you made these yourself or is there a recommended place to get these from?

looking forward to chatting to others who understand.

Thank you, Lisa