Clearly I have much to learn on fare bases. I just looked at the itinerary in Matrix and it actually shows the flight as just $1457, booking into Q class. On united.com the $1600 fare books into V class. If I tell united.com to use Q, it comes up as $1620.
I'll just wait and see what happens over the next couple months, but if it goes back <1500 then I'll book. I still feel like I don't understand how this all works. Is there a good resource that covers how it all works?