Thanks for all the quick and helpful replies! Tonight I had an agent on the phone who said "let me move you", but then couldn't actually do it! Drats!!!
Update: Super nice Gate Agent in LAX (very sassy to everyone and I just stood there and laughed and listened). NO PROBLEM on the upgrade! She never even said "I shouldn't do this....".....
And now I can start a new thread on how awful the F seats are on the PS 757's. Uggg! So uncomfortable and not truly a lie-flat product.
and last update: just checked my MP account and Elec UG's...she didn't charge me for the UG!