OK, but here's a warning for changing flights on united.com.

After you change the flight, and reprice, and even enter your credit card and pay for the change, IT DOESN'T COUNT YET. According to UA, the process still involves a live person checking your itinerary, making sure everything is ok, THEN confirming it.

My headache started when the live person confirmation didn't come until the next day, when the new itinerary priced out different than what I was charged by united.com. They then charged my credit card over $500 instead of the $159 united.com had sold me at. Fortunately I checked my credit card charge online and found it, but it still took finding the right person in Chicago to fix it.

My advice is if you proceed make sure you print out every screen in the process, especially pricing and confirmations. Until you actually fly you can't be sure what united.com will do to you. Godspeed young man. ^