But as West Coast is pointing out, it matters when the injury happens.
If you break an LOI, you serve the Basic Penalty (you sit a year and simultaneously lose a year of eligibility), and then you have four years to play three. So if EV gets injured in fall camp of Year 2, before he ever plays a down, he still has three years. If he gets injured during the season, he probably loses the year of eligibility (unless he gets a hardship waiver) and has only two years left.
**Note: I've seen it reported that if you break an LOI, you sit the year penalty, and then you have three years to play three. However, the vast majority of people are reporting that you have four years to play three, so I believe that to be the correct interpretation of the rule (I tried to look it up on my own, but the LOI is ambiguous on this point, so I'm relying on others' interpretations).