I would just go and try to pick it up. Every pharmacy that I've been to (here in the U.S.) has been ok with me picking up meds early. I believe that there is like a 20-25 day window after you pick up a prescription before you can refill it. But if they let you call in a refill, then it shouldn't be a problem picking it up early, if it's ready. One day shouldn't make any difference. You aren't the first person to go on vacation (or drop a pill on the floor by accident and run out early) Have fun!