Because the SEP firmware is rarely compatible across major iOS versions, saving blobs has become less of a "magic bullet." Even if you have the blobs for an old version of iOS, if the currently signed SEP firmware isn't compatible with that old version, the restore will fail or result in broken functionality, such as a disabled Touch ID or Face ID. Conclusion
SHSH blobs play a vital role in ensuring the security and legitimacy of iOS firmware. While they may seem like a complex and technical aspect of iOS, understanding SHSH blobs can help you make informed decisions about your device and its firmware. shsh blobs
Using SHSH blobs is not as safe as an iTunes update. You are actively bypassing security checks. Here are the common failure states: Because the SEP firmware is rarely compatible across
: If you saved blobs for an older version while it was still being signed, you can use specialized tools to "replay" that signature and trick your device into accepting the older firmware. Using SHSH blobs is not as safe as an iTunes update
Reverting to a faster iOS version if a new update slows down an older device.