Downgrade from iOS 6 to 5.1.1 can be applied or not? MuscleNerd the well-know iPhone hacker of iPhone Dev-team has just replied this question in a blog post. MusclNerd, talked about iOS 6 jailbreak as well. So let me break down this valued information to make it clear for anyone asking about downgrading from iOS 6 to 5.1.1 or any lower iOS version.
MuscleNerd is pushing iUsers to backup iOS 5.1.1 shah blobs now while they still can. Within few hours you won’t able to save iOS 5.1.1 shsh blobs.
Most of iPhone 4S, iPad 3 and iPad 2 users won’t be able to downgrade from iOS 6 to iOS 5.1.1. If they updated their devices to iOS 6 they will be stuck there without a jailbreak for now.
A few months back we released a redsn0w feature that lets you downgrade A5+ devices from 5.1.1 to anything lower (if you had saved blobs). Unfortunately once the 5.1.1 window closes, *redsn0w’s 5.x downgrade feature will no longer work.* Most A5 users will not be able to downgrade. So if you’re an A5+ owner up at 6.0 when the 5.1.1 window closes, you’ll be stuck there without a jailbreak for now.
iPhone 4, 3GS and iPod touch 4G will be able to downgrade from iOS 6 to 5.1.1 or lower always and their devices will be jailbreakable as well. iOS 6 jailbreak for those devices will be available once Cydia and other important pieces are all working efficiently.
A4 devices and 3GS will always be downgradable (and jailbreakable) due to limera1n. The tethered iOS6 jailbreak for those devices (and untethered for old-bootrom 3GS) will be out when Cydia and other important pieces are all working properly
iPad 2 owners who have both 4.x blobs and 5.x blobs will be able to downgrade between those versions only. If iPad 2 users update their devices to iOS 6 you won’t be able to downgrade from iOS 6 to 5.1.1 except in one case, you MUST have both 4.x and 5.x blobs to qualify for the downgrade from iOS 6 to 5.1.1.
iPad2 owners who have both 4.x blobs and 5.x blobs will always be able to downgrade to those versions, even once you come up to 6.0 and the 5.1.1 window closes (don’t do that yet though!). You need both 4.x and 5.x blobs to qualify for the downgrade even if you only wish to downgrade to 5.x
iPad 3, iPhone 4S and iPad 2 who have saved iOS 5.1.1 shah blobs only, will be always able to RE-restore to iOS 5.1.1 (restore from 5.1.1 to 5.1.1) and the same on 5.0.1 and so on. Once you update to iOS 6 you will be stuck there until releasing jailbreak.
iPad3, i4S (and iPad2 owners who don’t satisfy #2) will always be able to RE-restore the current 5.x OS that’s already on their device. So if you’re at 5.1.1 when the window closes (and you’ve saved your blobs), you’ll always be able to RE-restore to 5.1.1 again. This makes the 5.1.1 jailbreak a lot less fragile — you don’t have to worry about messing up your install with funky extensions or getting into a boot loop, because you can always RE-restore from 5.1.1 to 5.1.1 again (or from 5.0.1 to 5.0.1 again, etc). But once you fall off the 5.x train by restoring to 6.x, you’ll be stuck there until the next jailbreak.
Unlockers, you MUST stay away from upgrading as this will upgrade the baseband to lockable baseband
Please be aware that RE-restores and iPad2 downgraded devices will always end up with the latest baseband (not the one that came with that firmware). So don’t go near any of this if your unlock depends on the baseband version.
iPhone Dev-team will release new version of Redsn0w to let you able do the above features very soon.
All of these features will be released shortly in a new version of redsn0w. In the meantime please be sure you have your 5.1.1 blobs and stay at 5.1.1.