CREATE TABLE table_22815 ("Episode title" TEXT, "Subject" TEXT, "Music by" TEXT, "Lyrics by" TEXT, "Performed by" TEXT, "First aired" TEXT)

What is the date for the episode performed by Sue Manchester?
SELECT "First aired" FROM table_22815 WHERE "Performed by" = 'Sue Manchester'
SELECT "First aired" FROM "table_22815" WHERE "Performed by" = 'Sue Manchester'