Originally Posted by ricardoropez
You meant my device cannot flash to JB ?
No method can help me for change from
Kitkat to JB.
as mentioned by ultramag69,
unfortunately the upgrade of the Android O/S since 4.3 and above is irreversible (one way ticket), due to sammy is keeping on developing its bootloader.
Not only saying 4.3 to 4.4. Even the same version of 4.3 got few bootloader patches, and the same 4.4 also have few bootloader patches. This bootloader things make the upgrade irreversible. Downgrading can cause you to bootloop (soft brick), & KNOX trip.
and there's no KNOX friendly root method for the newer bootloader 4.3 and above. If you need root, you will have to bear with the KNOX trip. If you want to keep the KNOX, don't root, and just use your device as per normal usage.