I met a boy once that played one year at a D-III school, then 4 years at a D-I school. At first glance, that would seem to violate the 4-year eligibility rule. However, in his second year at the D-I school, he only played the individual fall events, and played no dual matches that spring but instead was listed as injured. I understand that D-III has it's own set of eligibility requirements, and transferring to D-I has a complex set of rules. I don't really know the boy or his family well enough to ask, but I'm just curious if it's possible that he discovered that there was an eligibility issue at the D-I school, and intentionally sat out that second spring to avoid violating rules, and keep his eligibility clean for his last 2 years. If so, it was probably a smart move.