So I need some tips on what to spend the travel credit on. I have an upcoming flight on Sunday BUT I purchased one of the two seats with an AMEX Delta companion ticket so, it has made the whole itinerary non-upgradable. The only thing I can think of is buying mileage booster (would that even work?) which is $0.02 / skymile or something like the internet day pass, which I don't really need.

Any other last minute ideas I should try? I thought about a United MPX purchase to try via SM, any luck? Thanks!