User blog comment:Aaronsclee/When is the Hogwarts acceptance letter posted?/@comment-82.10.196.154-20120130204637/@comment-68.226.202.135-20120201123025

I don't think the letter can be sent on the child's 11th birthday. A child must be 11 before the start of term on September 1st, so if a child were born in the middle of August, he or she would not be able to send a response by July 31st. Also, Harry's birthday is July 31st, and he received numerous acceptance letters when he was still ten. I'm leaning toward the 'letter sent in early July'