You miss 100% of the shots you dont take. He can always revert to the more standard programming, so why not go for it if hes enthusiastic? A little extra difficulty could be exhilarating.

The school sounds supportive. Id have him do both concurrently to minimize gaps and test out of the higher level class at year end, thinning out the amount of duplicate practice along the way. The worst case scenario is that he remains on track with a head start from extra exposure. He cant lose.

What is to give light must endure burning.