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I am surprised you find it hard to upgrade on United. Most people can upgrade on flights to Asia and Europe using a systemwide upgrade (SWU) or miles with no problem (even those people who don't have status under Mileage Plus). If you look on the United thread you will see that United will clear all of the passengers using SWU's and miles before allowing employees (when traveling for pleasure), their families, and friends to clear. What has been your experience?