You still can search for R availability through the "advanced Search" feature when you make a flight reservation:
Checking the box that says "MileagePlus Upgrade Award". It will give you a yes/no answer if there is R availability for the number of passengers requested. It is more cumbersome but it at least gives you the information if there is R availability.
However, it doesn't show how many R are available. But you can figure it out by adjusting the number of passengers and seeing if there is still availability incrementally.
Last edited by sfonorth; Sep 8, 2012 at 9:45 pm