Thank you for your concern.
League structure that was impossible.
I'm sorry for not testing.
League structure be modified :
20 teams, 2 subleagues.
Sub league 1 : 2 divisions of 4 teams -> 8 teams
Sub league 2 : 2 divisions of 6 teams -> 12 teams
2-game series. It's okay!
Give me an update if another problem being..