Interesting commentary about elite upgrades not being processed at T-24 when U space is available...my two most frustrating parts of the whole U space mess continue to be....

1. U space immediately going to zero when one U seat is taken--makes using upgrade certificates on separate PNRs nearly impossible.
2. Selecting "upgrade certificate" eligible fares on a round trip only to have one segment in an ineligible fare class--recent IT bug but annoying nonetheless.