iPhone 4S, iPad 2 and iPad 3 users will now will able to downgrade to any firmware iOS 5.0.1/ 5.1 using the upcoming new method implemented in Redsn0w 0.9.11b1(most probably). Musclenerd from iPhone Dev Team has confirmed that the next update of Redsn0w will allow A5X devices users to restore to firmware without using iTunes.
In proof of his work Musclenerd has posted an image showing redsn0w 0.9.11b1 restoring iPad 2 to iOS 5.0.1.The one and only requirement to downgrade your iPhone or iPad is that it will use the saved SHSH blobs for processing. So, if you don’t have saved SHSH blobs for the firmware to want to downgrade to, then you will not be able to downgrade.
Upcoming redsn0w supports restoring, including iPad2/3 and 4S downgrades (with blobs) twitpic.com/9ixsqv ..also stitches on the fly
— MuscleNerd (@MuscleNerd) May 9, 2012
And users will not be able to downgrade to any firmware prior to the initially preloaded firmware of the device. That means, if you have an iPhone 4S pre-installed iOS 5.1(at the time of purchase), then you will not be able to downgrade to iOS 5.0.1.
However, the image depicts that the most of the work is complete for the updated redsn0w but still there is no exact ETA shared by Musclenerd. But the release is quite close as it seems to be just in testing stage. We will provide all information related to the release, just connect to us on @Jailbreakwire, and Facebook Fanpage for get immediate updates.