How long did Austin Cintron take to return the movie 'Destiny Saturday'?
'Destiny Saturday' refers to title = 'DESTINY SATURDAY'; length = subtract(return_date, rental_date)
SELECT T2.rental_date - T2.return_date FROM customer AS T1 INNER JOIN rental AS T2 ON T1.customer_id = T2.customer_id INNER JOIN inventory AS T3 ON T2.inventory_id = T3.inventory_id INNER JOIN film AS T4 ON T3.film_id = T4.film_id WHERE T1.first_name = 'AUSTIN' AND T4.title = 'DESTINY SATURDAY'