It is worth advocating with the school for your DS10 because 99th percentile using independent school norms is a really good indicator of his mastery of core subjects - in our case, my son got similar scores at ages 7 and 8 and the school automatically accelerated him in LA and math without any requests on our part. They said that their policy was to accelerate when CTP4 scores were so high because they did not want student boredom in class.