Originally Posted by
jsguyrus
Never book a first upgradable fare unless U space is available, it's just wasting money. Should U space open up, you just call in and upfare to whatever class you need to use your GGU.
Yep....the whole point of telling you if U space is available or not is basically so you don't have to waste your $$ buying an upgradable fare that doesn't have U space available.