I was at Pengam from 1964 to 1971 and the court was always busy. The top rugby field was behind your back as you played and our version meant that as many as 20/30 would be on court at any one time. The server and receiver started the game as usual but if the ball stayed up after both had played it then the next person to play would enter the court, and if he kept the ball up then the one behind him played until the ball was down. At this point the person hitting it down left the court and the server and receiver restarted the game. This continued until just the server and receiver were left and the final played out. If the ball was kept up by all the players then after the last man played his shot the next in line played his, eventually going down all those left in until the next downed ball. 
As the rugby field was on higher ground, the queue of players waiting their turn would quite often extend up the banking.