You can be denied terminal leave or separation leave. A guy I worked with who retired had his terminal leave shortened. It's at the discretion of the command. My command typically only allows 14 days of terminal or separation leave, though in the past year, this has become a bit more lenient and the CO is allowing more depending on the staffing situation. Ultimately, it's up to your CO. I got 2 weeks approved. Fortunately, I didn't go in with high hopes! Remember, the military is not required to let you take leave of any type, just liberty (ie, they have to let you go home from work or to rest at some point). So if you're planning to get out and don't want to take the financial loss of selling leave back, start far in advance and take your leave!