When does United open up seats? Context: I'm trying to make frequent flyer reservations 331 days out and having trouble grabbing the couple of seats in business that have been allocated. Thus, do seats get loaded into the computer at midnight; 6 a.m., 10 pm? You get the idea -- and what time zone.

[I'm pretty sure this information is out there already, but I've done a couple of searches and come up empty.]