thanks guys, I did just that. I got the fc upgrade by paying the difference rather than what the website was buying me to 'buy up'. With the 24 hour cancel window its a no brainer. The only catch is that by cancelling and rebooking technically I would have been submitted an expense report for a different flight ID than I actually flew. Was glad they gave me the actually difference instead of the 'upgrade' price on the web so everything is clean. Still I wish the upgrade price against the reservation was the actual difference instead of so much more.