Two-time Apollo commands-who could've gotten one?

One of the reasons Wally Schirra left NASA when he did was that Apollo 7 was likely to be
his first and last Apollo mission. ISTR reading about Pete Conrad after Apollo 12 trying to get
Apollo 20 before it was axed, and if he couldn't get it, he was fighting for Al Bean to command
20. Had Wally stayed in NASA, would he have been considered for a later Apollo? And had
18-20 been funded and flown, would Pete have gotten his way in either him taking 20, or
failing that, Al Bean taking 20? I realize this is all hypothetical, but what-ifs are always fun
to think about.