Originally Posted by
joe_miami
You should be able to buy up to F on your exact same flights by calling United and asking to do so. They waive the change fees when the itinerary is the same and only the fare class is changing.
Well, unfortunately because the ticket was purchased by a gov't agency, the United CSR says I can't buy an upgrade to first class. I'd have to go through the NIH travel agency, but of course they don't buy first class tickets for patients. So looks like I'm stuck hoping the miles upgrade goes through.