My son and his friend went to Jupiter in their junior and senior year falls. Both got the most interest and offers after the senior year showcase, so it is definitely not too late. The only coach their senior year who seemed to signal that he was already "done" with his recruiting for that year, was Princeton's (just implied, I don't know for sure). I imagine it may vary from year to year, but a lot of these schools really do focus on the seniors I think.