So, my partner and I are hoping to fly 8/23 IAD - ATH and return 9/4 IST - IAD. I want to use an award ticket for him and a paid ticket for me. I am finding decent Z fares IAD - FRA rt (figuring I could either buy a separate intra-European ticket or awards on LH/A3/TK for me). The challenge: there is award space at 67,500 miles in F or 125,000 in C each way, but if I buy Z, I can't GPU the Z to F. I don't want to use 250,000 miles for a C award. So, my question: Can you voluntary downgrade an F award to C in advance (we would like to sit together)? Is there another way to upgrade Z to F? What advice does the board have for me?