I can't help you with a child in your area stating this year but can reassure. My DS started at STRS last September. He knew one other child but wasn't particularly friends with him. And he and us were anxious about the change.
However the school is awesome at making the boys feel welcome and runs a totally epic induction programme. He has made loads of mates and is very happy and literally thriving at the school. And out of school he meets up with friends regularly.
The faculty are brilliant: really focused on both pastoral care, creating citizens as well as academic outcomes. My DS was one of the ones welcoming others at the recent fitting evening and from the little he has told me and DH he raved about the school as well as advising parents on how many pairs of rugby socks to but!?!. And he is not unique in terms of loving the school and being very happy there.
It may only be words at this stage but I am sure your DS will make friends quickly and settle in. It is scary but I suspect before long you'll be thinking that the taxis service to visit new friends and undertake the new school activities is taking over your life! But in a good way.