Note, I was NOT asked for PNR when requesting these certs in January 2013.

No problem IN THEORY with supplying the info. The problem comes when you don't get the upgrade and have to ship the paper cert back to UA, presumably as certified mail. What a time hassle and expense. If you had a backup flight in mind for the succeeding few days, it just can't be done.

Are they trying to eliminate these certs entirely?