Question: What was the main date of the round with 20 fixtures?
SQL: SELECT "Main date" FROM "2-17814838-1" WHERE "Number of fixtures" = 20.0;

Question: What were the new entries for the Semi-Finals round with fewer than 8 fixtures?
SQL: SELECT "New entries this round" FROM "2-17814838-1" WHERE "Number of fixtures" < 8.0 AND "Round" = 'Semi-Finals';