Apple Apple has stopped signing ios 5.1.1 blobs

[yusuo]

This is basically just a little heads up, found out as I just upgraded to ios 6 to have a quick look, was planning to stay with but the lack of jailbreak apps kinda makes me want to go back plus theres not really anything special.
Anyway to the point was trying to use a unsigned ios 5.1.1 ipsw and it kept throwing me errors, so tried my stiched file and voila it works.
So it looks like Apple have officially stopped people from going back now, so make sure you backup your blobs before you even try to upgrade now

 

[BORTZ]

ALWAYS BACK UP YOUR SHSH BLOBS PEOPLE

I feel like that cant be said enough.

 

[Izen]

Note that you can only back up your 5.1.1 (or any firmware) SHSHs from your device if you are currently running that firmware on your device and your device is vulnerable to the limera1n exploit (so everything released before the iPad 2, iPhone 4S, and iPod 5G) using iFaith. Cydia usually backs up your SHSH file for you for every major firmware release, provided you actually ran Cydia when Apple was signing those firmwares. You can use TinyUmbrella to do that in a much more reliable manner yourself.

You should save the SHSH blobs for as many firmware revisions as you can. The files are 6 KB each, so it's not like they take up any real amount of space on your hard disk or a flash drive, and a lot of firmwares do things that other firmwares can't. 5.0.1 is the only firmware that you can use Spire on, which is a perfect Siri port for every device as opposed to the glitchier Siri alternatives for other firmwares. 5.1.1 fixed a lot of battery life and cell reception issues devices were having on 5.0.1 and 5.1, and is also the latest release that can be jailbroken untethered on all devices (except the Apple TV 3). 6.0 has a lot of new stuff, and even though there's no untethered jailbreak for it yet, there very well might be one in the future (though I would bet on the devs waiting until at least 6.0.1). The point is you may want to be on an earlier firmware than Apple is signing for any number of reasons, but it's currently impossible to restore to them without your SHSHs saved. Just back them up. It doesn't hurt, and it certainly helps.