Originally Posted by
ORDnHKG
10 years ago if you try to upgrade with miles internationally, first you have to buy H class and up fares, then you have to waitlist. However, if your upgrade don't clear, only your miles will be refunded, but your H class sticks, so it means you pay H class for nothing.
I remember those days. However, back then when I did this, the upgrade percentage for me was about 90% so didn't mind getting stuck with a "H" class one out of every ten flights.