(adsbygoogle = window.adsbygoogle || []).push({}); You could possibly, hold teh power button for really long till you get some sort of menu which lets you restore your system. If there is an option to restore from USB, we could be getting somewhere for the PSUPDAT file is in the Jailbreak.

You me recovery mode

I tryed to use Proxy to redirect the online update an no luck. It will stop in the download and say the .pup is not supported.

I was thinking u could downgrade that way

Proven not to work, a long long long long time ago.