Just helped family book a pair of tickets in K and Y classes. One traveler is Gold, and U space was open on two segments. It should clear instantly (or near) at booking. The Y segment cleared instantly, the K did not. I messaged AS and learned two things:

1) The K fare issue is known (not sure if its lower classes for Gold, or lower classes for all status levels), and
2) The leads still can override the upgrade processor manually and make it happen (at the expense of breaking OLCI when you travel.)