So far iPhone 4S (actually including 4,3gs) cannot be restored to 5.x, but we have decided to release an update to Tinyumbrella 5.01, so that at least shsh of ios 5.0.1 can be saved (already supported iphone 4s), although it is not of much use to us now, but as the information is updated we will update to support the latest shsh save and restore.
Of course, the developers of TinyUmbrella have already told you the reasons why you should save SHSH blobs. That is to say: Whenever a new firmware comes out, Apple will stop verifying the old firmware, so that it cannot be restored to the old version of the firmware (referred to as unable to downgrade).
Therefore, it is recommended that the shsh of the current firmware should be saved in time to prevent accidents. It will be very useful if you need to restore it at that time (although it is said that the verification will change after iOS 5. But before the new verification method is determined, this is the best way)!
As usual, if you have a problem during the backup process, please select "Request SHSH from Cydia" in the advanced options. It is recommended to back up for easy restoration. To back up the iPhone's SHSH, useTinyUmbrella Back up SHSH.
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