6'3, 175 throwing 88.....if he has a good showing at Jupiter, he may not need the summer of 2018. If he can be ready, I'd go ahead and do it. You won't find another opportunity to be seen by that many coaches/scouts until next July. Why wait, unless you're really concerned that getting back in throwing shape is going to be a problem. Kids like that will get noticed. As someone else said, make sure to contact any coaches who have expressed interest (or that your son is interested in) and let them know he'll be in Jupiter. Then follow up once he has an idea when he'll throw. It would be great if he's a starter and his team can tell you his spot in the rotation ahead of time so you can promote his start to coaches.