Here we are 3 years later and still no response. Today I had a lengthy conversation with EA and also with a rep from Xbox Live (who seem to be very upset with this situation and gave me a specific login to a complaints area).
The EA support told me that it is Live's fault, that I shouldn't change my Live account to adult as that is breaking the user agreement with Microsoft (it isn't) and that this is the law (is isn't).
So I then reported EA to PEGI for incorrectly stating the law and blatantly ignoring the issue or passing the buck.
A quick summary for anyone having this issue.
EA say the law states that a child of 10 can't play a game with a PEGI rating of 16. This is false. The rating is there as a guide to parents to help them decide what is best for their child. This is Star Wars.. enough said.
EA say that it is out of their hands and is an MS Xbox Live issue. This is false. Even if you open the account to adult allowances you still can't get access to the MP part of the game.
EA say that it is against the MS user agreement to change the account from child to adult. This is false. The option is there for a reason, it is to allow you to decide what content your child can have access too. It is completely your choice if you wish to remove all child restrictions and open up as an adult.
EA state that it is clearly noted on the packaging that you must be the correct age to access Live content. This is false. I have the box in my hand and it does not state this anywhere.
I will continue to report EA where I can until they address both this issue and their staff clearly giving our incorrect legal advice.