UNSAT is 2 D's, 1 F or a cumulative QPR rating under 2.0 for upper class. For plebes, its just 1 D because their academics are so much easier than everyone else's. I believe thats just for 6 and twelve weeks though, not semester. Luckily I've never been unsat though so I'm not an expert.
As far as restrictions for unsats, they rate the liberty policy of the class below them which for a plebe is still just plebe liberty, they don't rate weekends, and they also have to do actracking which is basically a log of studying. I think they should still be able to play with the team though they might not be allowed to travel if they don't get significant playing time.