I'm sure this is answered somewhere but I couldn't seem to find the exact right search term.

I booked an award ticket with UA miles. It's PHX-LAX-LHR. 80k miles but mixed class. PHX-LAX is in economy and LAX-LHR is business. I'm very happy with what I have but I'm curious about if I should do anything to be eligible for business/first on the PHX-LAX leg. I've tried to read up on how that would work but I'm not sure I understand what, if anything, I need to do. I've seen info about calling to make sure I'm listed on the upgrade list as, I think, a "displaced first class passenger" or something like that. And then if not upgraded by 24 hours before the flight, making sure the airport upgrade list is coded correctly for me.

Again, I don't care if I sit in economy on that short hop, but if I'm eligible to even be considered for the upgrade, I'd like to make sure that the right boxes are checked, so to speak.

Also, as a side note, even if I'm in economy on PHX-LAX, I should still have access to the UA lounge in PHX because of the business class LAX-LHR, correct? And I know about the Polaris lounge at LAX. 😊😊😊
Thanks.