Well, it makes a big difference about being able to use what clearance she has if you are unsure about how she is being separated. The conditions of separation can affect future clearance status, particularly with less-than-honorable situations.
If her clearance status is going to remain good, then almost any degree in a non-liberal arts discipline would help her. She could even get a government GS-level job where they possibly help complete her degree work.
The clearance ends when her military service does.