When did the season start that ended with the top record of Lindenwood (20–0–0)?
CREATE TABLE "division_i" (
  "no" real,
  "season" text,
  "championship" real,
  "no_of_teams" real,
  "start_reg_season" text,
  "finish_incl_championship" text,
  "top_record" text,
  "national_champion" text
);
SELECT "start_reg_season" FROM "division_i" WHERE "top_record"='Lindenwood (20–0–0)';