MEPs restart at the beginning of the calendar year, has nothing to do with programs. As long as you're classified as a intern (assuming it's not Management), you fall under seasonal, which means your MEP will not be "reactivated" for the new year until you work your first shift of 2012.
Probably won't be a problem for your since you're currently in a program and likely to work at the top of the year, just wanted to give a heads up for anyone else that may be reading.
Are you going from a PI to PI or CP to PI? I went from CP to PI and my area let me go seasonal for the week inbetween. However, I know other people who were "unemployed" during their breaks. If you get the "unemployed" status, then I'm not sure how that would affect your MEP. They may mail you a new one with the start of your new program?? You may want to touch base with your Managers.