By reading the description? If you're flashing a TouchWiz based ROM that is on 4.1.2 Jelly Bean, you can flash that only if you're NOT on the MJB bootloader. If you're on the MJB bootloader, you can only flash 4.3 TouchWiz based ROMs.
AOSP does not matter, at least to my understanding. You will more than likely need to upgrade CWM or TWRP if you plan on flashing AOSP KitKat ROMs. If you don't, you'll get an error when flashing that can only be resolved on the latest versions or CWM or TWRP.
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