I'm sure they would understand if you rescheduled as not to hinder your MCAT performance. If your travel experience is anything like what mine was, it will take a few days to recover. You may be fine with the traveling, but if this is your first attempt with the MCAT, maybe reconsider. I know a guy at another med school that received a conditional offer of acceptance- that condition was a higher MCAT score. Not saying this will be the case with you, just my two cents. Congrats on the II, and best of luck on both items in your future. I interviewed Oct 16th and loved it. Eagerly waiting by the phone all day everyday.