You imply that he's a PO, and if so, he should take a few months off from throwing each year, IMO, and fall is often the best time for that.
He's not a PO yet (he has a good arm in right field and does fine at 1B) but clearly pitching is his strong point and his future, so PO will happen eventually.
He does take a minimum 3 months off from throwing each year - which is a big reason I'm not a fan of fall ball. I also religiously track pitch counts. An advantage of being small is that he has not been pitched excessively - that honor usually belongs to the big, early developers who throw hard.