American carriers generally roll out software updates after majority of the users with international variant have received it. But Sprint has started rolling out the Android 4.3 for the Galaxy Note II just a day after Samsung started rolling out for the international variants.
The PAMK4 update that users will receive through OTA will bring the Android 4.3 update along with support for KNOX, Galaxy Gear and some HD Voice enhancements.
The update will expectedly be rolled out in phases so hang on if you haven't received the notification right away.