When DevTeam has released another update of Redsn0w which supports the downgrading process for iPad 2, iPad 3 and iPhone 4S for the saved SHSH Blobs of the lower firmwares, TinyUmbrella has been updated as well. With the help of TinyUmbrella, you could save SHSH Blobs on iOS 5.1.1 which is the latest firmware from Apple.
After a statement from @Pod2G on twitter that iOS 5.1.1 untethered JailBreak would be made public in weeks, it’s actually important to give it a shot right now. Once Apple has pushed iOS 5.1.2 or iOS 5.2, you wouldn’t be able to save the SHSH Blobs for the lower firmwares. This is because Apple would close the signing window within hours.
Also, semaphore, the developer behind TinyUmbrella warned that you shouldn’t select “overwrite SHSH” and “request SHSH from Cydia” in TinyUmbrella. It would overwrite your APTickets/SHSH Blobs over the pre-existing ones. However, he would release an update which won’t do that in near future. To be on the safe side, you could also save SHSH Blobs on a different disk from the default folder, so that they are not overwritten accidentally.
Download TinyUmbrella from here