CREATE TABLE table_22641 ("HR no." TEXT, "HR name" TEXT, "CR no." FLOAT, "LMS no." FLOAT, "Built" TEXT, "Works" TEXT, "Withdrawn" TEXT)

When 2/1939 is the withdrawn when was it built?
SELECT "Built" FROM table_22641 WHERE "Withdrawn" = '2/1939'
SELECT "Built" FROM "table_22641" WHERE "Withdrawn" = '2/1939'