That's not true, I got this from one of the TC Fall tournaments:
++++PLEASE REMEMBER THAT YOU WILL PLAY AT YOUR 2011 AGE GROUP FOR ALL OF OUR 2010 FALL EVENTS. FOR EXAMPLE IF YOU PLAYED 10 AND UNDER THIS PAST SPRING, THEN YOU WILL PLAY 11 AND UNDER THIS FALL 2010 SEASON++++
I think the confusion with TC might be that they tend to have a couple of "Last Chance" tournaments in the fall, where your team can play at last year's age one more time.