Each year the four lowest-placing league members lose their places in the league. Their replacements are selected through knock-out preliminary tournaments, with the bottom finishers in the league seeded into the final stage. For example, in the 76th edition Sada Atsushi scored 2-5 in the league and was eliminated, then in the 77th edition he beat three opponents in the final preliminary and regained a seat in the league.
The loser of the title match becomes a league member for the next year's challenger selection.
The league is going to be abolished after the 78th edition.