CREATE TABLE table_75586 ("Name" TEXT, "Pennant number" TEXT, "Builder" TEXT, "Laid Down" TEXT, "Launched" TEXT, "Commissioned" TEXT, "Current status" TEXT)

what builder is now retired
SELECT "Pennant number" FROM table_75586 WHERE "Current status" = 'retired'
SELECT "Pennant number" FROM "table_75586" WHERE "Current status" = 'retired'