In 2007 my younger son was just certified J.OW Padi.
We went to Cairns, Australia on a LoB, where he was certified J.AOW.
During training, the "deep" dive was around 25m.
After getting the J. AOW he was allowed to take part to the deepest dive of the 11 planned, which was 30m.
After coming back to Italy he did dive routinely to 30m and was considered an "advanced" diver everywhere.
But when this happened, he had already more than 100 dives, despite he was just 12. He started diving at 5...
So my suggestion (following
@tursiops ) for your son is to take the AOW first. Then he can continue with other specialties, "deep" being one of them, when ready.
But in most places, they will be happy with an "advanced" certification.