Tried to buy a ticket this morning.
After selecting flights, did not allow me to choose E+ seats. Though on the bottom of the page it says "Economy plus - included" (Yes, I qualify for free E+ seats on UA).

lets me select E- seats.

Whatever.
Will try buying it later...

Of course, I can buy now and call in for the seats. Not in the mood to call UA.

Most of us will lose our jobs if we produce such an error-prone product.