From the Knowledge Base:
At DI schools, the player will only have 3 years of eligibility (depending on their collegiate gpa, they may be granted a 4th year of eligibility if they maintain a 2.7 cumulative GPA or higher) - in both situations, if they choose to play their 4 year of eligibility they will be playing as 5th year Seniors. At DII schools, the player will have 4 years of eligibility. In both situations, they will be eligible to play beginning with their sophomore year, assuming they have a cumulative GPA of 2.0 or higher after their freshman year. .
If I'm reading this correctly, D1 players need a cumulative GPA of 2. 7 in order to the the 5th year. But DII players get the 5th year anyway. But it's not worded very clearly