I was attempting to book a simple roundtrip this morning on united.com, SFO-LAX-SFO. When I got to the seat selection pop-up, there were no E+ seats available; strange, I thought.
So I checked random other dates in Jan., March. No E+ seats available to me. I am Premier, have been all year - could it just be a bug? I am logged in and using my profile for the booking.