Updating firmware through SEUS clears sim lock patch?

[sergage]

New CIDs are deployed from time to time, for the sole reason of preventing them from beeing unlocked/flashed/tampered with by non-SE service tools.

So are there any offical SE tools (besides SEUS) with which one can flash a phone using desired MAIN and FS and such?

i have a k850i which have been upgrade to CID53! is there are any tools where i can downgrade back to CID 52??

The answer, unfortunately, is a firm NO.