I just ran into the "no upgrade available" error attempting to apply RPUs to LAX-EWR. Website would not let me apply them to the reservation. Had to call. And then the agent's computer insisted that he ask me all of my security questions. To apply my RPUs to a ticket in my name. Really high risk of fraud in that transaction

Agent suggested I contact web support to report the error. I responded that UA is well aware of it, it's been going on for months, their IT people are too busy writing code to further devalue MP to fix the website. Then I had to apologize for venting at him