I am currently on Snowbreeze 3.1.3 and would like to upgrade it to 4.0 and would like to know if there was a problem would i beable to put it back to 3.1.3 snowbreeze. The reason i want to go up is because i have noticed the battery does not to be doing as well as it did wh i was on 3.0 jailbroken with purplera1n. I am currently have the old bootrom im sure as it did not update with snowbreeze.

I have not got the SHSH and when i do go on cydia now it says i have only 4.0 or above nothing lower.
Hope this makes sense and somone can help.