Nope, not unless they changed the law. You can be sent overseas, to combat, but if you have a date for seperation from the service, you go home. In fact, keeping you on active duty beyond that date (without a declaration of war) cost the military big buck$. More, they have to pay you mileage from the place of your seperation from the service to the place of your enlistment UNLESS there is transportation available from there to there AT GOVERNMENT EXPENSE. Mind you, this is usually enough for a standby air ticket -- being seperated in, say, Ft. Lewis, WA and having enlisted in, say, Chicago get you enough money to fly home and perhaps a few bucks over. Of course, if there's an Air Force plane going from Seatac to O'Hare, and you can get on it, you don't get mileage money. Now, if you take the money and decide to stay in Seattle, the government doesn't care -- they've done what they said they would.

Certain MOSes (jobs) could be extended for a longer, but finite, period IF those jobs are declared critical and in short supply. This usually is for something like speakers of Arabic, etc.

Actually, I think that the military tries to be fair to the troops as much as possible. The politicians, on the other hand....