CREATE TABLE table_1066 ("Pos" FLOAT, "Member Association" TEXT, "Points  ( total 500 ) " FLOAT, "Clubs" FLOAT, "Group stage" FLOAT, "Play-off" FLOAT, "AFC Cup" FLOAT)

When the group stage has been 4 what is the largest playoff?
SELECT MAX("Play-off") FROM table_1066 WHERE "Group stage" = '4'
SELECT MAX("Play-off") FROM "table_1066" WHERE "Group stage" = '4'