I have a question about how Star Alliance Gold Air Canada members can upgrade on United.
Right now I am a 75k elite, about to become 100k super elite on Air Canada (although a lot of my miles have actually been on United flights).
How do I upgrade when booking a United flight? Does it cost me e-upgrade credits (or $ or miles?) And when do I apply for it?
Thank you in advance for any assistance.
If this question has been asked before, sorry for the clutter, and a link to the answer/thread would be greatly appreciated.