Since United Airlines and Continental are merging, there is a trick to bump
your United Mileage Plus expiration date out 18 months.
1. Create a Continental Airlines Onepass Frequent flyer account. Link: http://www.continental.com/web/en-US/apps/account/enroll.aspx
Make sure to use the same address as listed on your United MileagePlus
account.
2. "Merge" your new OnePass account with your United MileagePlus account.
3. Transfer 10 miles from UA MileagePlus to the Continental OnePass account.
Your MileagePlus expiration date will then be bumped.
Happy Travels!!