Doesn't sound like there are any limits. If you have at least 48 hours off, they will send you. If you feel like you can handle every weekend at home as opposed to sticking around and studying, by all means, visit the family.

One of the issues I see is that it depends on the route you are flying. I have looked on pass rider before, and seen the last flight out of MSP to a particular destination was 1507. Now, looking at the same flight, there are two more after that. So it all depends. But for sure, early booking is best.