I believe that the assumed advantage to the state of pushing back the K cut-off is two fold. One, it saves them $ on the kids who won't be able to enter K that first year it is changed making for a smaller than usual K cohort. That only lasts one year, though. Two, it makes the state more competitive on a national stage b/c their younger kids aren't being compared to older kids from other states on the same tests.

Anecdotally, we have seen a lot of the older kids who were red shirted labeled gifted in elementary due to being higher achievers than the kids who are 12-18 months younger than they are.