Hi all, I have been reading and learning a lot about airline miles over the past few months, but haven't learned enough to deal with a pressing question. I am a Premier Gold on United and am looking to book tickets for my parents to HNL in February. They would be travelling from IND or SDF and (hopefully) making a single connection through Chicago, IAD, Phoenix, etc. I have about 140k miles banked, so not enough to purchase outright awards ticket in business/first. My question is whether there is any way to know ahead of time whether economy tickets purchased with cash will be upgradeable using miles at the time of purchase? I am looking to upgrade the longer flight to HNL and the longer return leg. As far as I can tell, no, but I wanted to double check with the wise community here. Thanks in advance!