http://www.gsmarena.com/samsung_i9300_galaxy_s_iii-4238.php noted it did have that but upgrades have 2 paths.

1. The carrier or maker issues it.
2. You decide to root it and head to xda forums (I don't offer rooting support anywhere.)

Keep in mind that no one I know offers support for this but I have done other models with some research of the xda forums.