Sorry, I should have been more clear. You don't have to serve a day after your commitment as long as you submit your paperwork 6 months prior to your separation date.

One thing I forgot to add...if you are planning on taking terminal leave, you have to add that many days to your 6 months prior. For example if I am taking the max 60 days I would actually have to drop my paperwork 8 months prior to my date of separation or end of commitment. With the way things look right now I will probably do all my time and sell back my leave since the job market doesn't look promising.

Jousteagle is right, if you have completed your ADSC your commander can push for an earlier date. At that point I think it would be determined by how much your commander likes you/willing to go to bat for you. The regulation specially mentions things such as being able to meet hiring windows or certain restraints of future jobs as reasons for less than 6 months notice prior to separation.