How many series premieres did the season "All-stars" have?
CREATE TABLE "table1_2311410_1" (
  "season" text,
  "episodes" real,
  "series_premiere" text,
  "series_finale" text,
  "winning_couple" text,
  "winning_profit_aud" text,
  "host_s" text,
  "judges" text
);
SELECT COUNT("series_premiere") FROM "table1_2311410_1" WHERE "season"='All-Stars';