I'm not sure if it is printed on Mazda's manual when the ATF should be replaced. However, I think I will follow my old practice of changing it every 40,000 km.
madalas naka indicate sa manual na "no need to change ATF" if driving under normal conditions.
kung under "severe" which includes city traffic, long idling, bumpy road conditions, short trips. need to change ATF. some manufacturers recommend to change at 40K kms, some suggest to change at 90k kms.