CREATE TABLE table_23026 ("No." FLOAT, "Country" TEXT, "Local title" TEXT, "Format" TEXT, "Start Date" TEXT, "End Date" TEXT, "Episodes" TEXT, "Premiere/Air Dates" TEXT)

When did the season with 1 team format premiere?
SELECT "Premiere/Air Dates" FROM table_23026 WHERE "Format" = '1 Team'
SELECT "Premiere/Air Dates" FROM "table_23026" WHERE "Format" = '1 Team'