MileKing, you are correct sir!!!

US Airways allows upgrades on free (bump voucher) or award tickets. Preferred members only, two hours before the flight, and you can only use purchased upgrades (or $$$). You can not use the complimentary upgrades sent to Preferred members.

I am fairly certain this policy is still in effect although not many of the ticket agents know it. I've had much better luck with the Club agents.