Since no one answered I am assuming no one knew the answer. So, in case others have the same question, yesterday while at the airport on another flight, I contacted a CSA for UA who had a moment and asked about it. I was told that you only have to list once in this situation. If they can not get you into the C cabin, they will roll you into the Y cabin and you can use the Y tix. Then you can save the c tix for another time or turn it back to the company for a refund....