Rules of the game:
Preliminary rounds are in the Robin round format, then top finishers go to the knockout stage. 
Round Robin format - players will be divided into groups and play each other. Winners and runners up in each group qualify to the knockout stage.
Preliminary rounds will be 1 set (6), no advantage and if 5 games all, regular tiebreak. Knockout stage will be fast 4, best of 3 sets, third set super tiebreak.