Generally for the single bay My Cloud, a P/N that ends with “-00” is first gen, runs OS3 v4.x firmware and cannot updated to OS5 v5.x firmware. Further indication that the Japan version has some additional differences than other single bay My Cloud’s who’s P/N ends with “-00”.
Edit to add: There was a table posted a long time ago that broke down the processors in the various models. Supposedly the Japan single bay My Cloud version uses the same processor (Marvell Armada 375 (2x1GHz)) as the second gen single bay My Cloud version.
