This article refers to education costs.
"A 529 plan can supplement these service-earned education benefits. If you split your Post-9/11 GI Bill benefits among multiple dependents, then a 529 plan can help cover the remaining qualified higher education expenses
associated with attending a two-year or four-year college, apprenticeships, trade or vocational school".
The ultimate authority is the IRS and they say this:
4. Made on account of the attendance of the designated beneficiary at a U.S. military academy (such as the USMA at West Point). This exception applies only to the extent that the amount of the distribution doesn't exceed the costs of advanced education (as defined in section 2005(d)(3) of title 10 of the U.S. Code) attributable to such attendance.
Pub 970
