My dd11 took it last year. I offered her a choice of dates and locations that I was willing to take her to. She chose to take the February test and it worked out well. This year, she will take the January test since the site is just around the corner (so no getting up too early!). I don't think it makes any difference to wait or not to wait, unless you have a child who will worry about it until it's over, then I would go for the earliest test.