If you are going to book multi-city you will need to call the awards desk. If you are willing to share with us your plans we might be able to tell you if it's allowed.

I'm not too sure what your status is with United, but you might want to take note of the award ticketing fees. If you're a 1K or UGS member you are exempt from the fees.

http://www.united.com/page/article/0,6722,50994,00.html

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