Sorry just have to ask. What is EUA...

Electronic Upgrade Application?
End of United?
Elephant Under Airplane?
Ear Under A**


>>Same deal on my EWR-CLT flight tomorrow, got 5-day EUA, but the app's flight status has 13/16 booked with no one upgraded. My BP is correct so I'm not sweating it, but interesting to see. Those on the upgrade standby list appear to be as before. <<

How do we know this? is this the new United Cell Phone APP?