e500 and flight standby
 

I am going to fly from DAY to LAX via ORD on 8/29. I will arrive in ORD around 7pm, but the next flight I got was the 10pm-ish flight to LAX (it was cheaper than some earlier flights). I was thinking of using my e500 for the 10pm-ish flight, however, if I decide to standby for the 8pm flight, can I still use my e500? How can I use it?

When you stand by, tell them you'd like to upgrade. If you clear standy and there's space in F, at that point they'll ask you how you want to support the upgrade.

Thanks for the quick reply. If I decide to do the standby using OLCI, I won't be able to tell UA about the upgrade until I get to the airport right?

What I do is use the e500s for the later flight. If you get the upgrade then when you standby for the earlier flight you'll be standing by for first class as well. If you don't get the upgrade on the earlier flight, but go coach instead, then the e500s will be returned to your account automatically. If you don't get on the earlier flight, then you've got your first class seat for the later flight.

Only if the GA doesn't know what they're doing. You are supposed to stand by in your ticketed cabin. Only after you've cleared that can you be considered for an upgrade.

Since you have to clear into Coach anyway, it doesn't matter.