Signing periods for iOS 10.2.1 may end at any time after the release of iOS 10.3. So now you have
There is no jailbreak for iOS 10.2.1, these blobs cannot be used for their intended purpose; it cannot be guaranteed that a jailbreak will ever appear. But if this happens, you will definitely need blobs, so do not wait and save them right now, when there is still an opportunity.
</ p>Downgrade on iOS 10.2.1 is only available to anyone using a newer version. Errors are fixed with each release of iOS, as a result of which the jailbreak tools stop working. Saving blobs in .shsh2 format for 10.2.1 is highly recommended because in the future you will probably be able to roll back to this version using Prometheus and apply the updated jailbreak.
Saving blobs for iOS 10.2.1
Who should do this?
Anyone should do this regardless of hisplans. It’s easy to save blobs, and you may need them at any time. They will help jailbreak users switch to 10.2.1 when a new version of the jailbreak is released. Save them right now and keep saving them in the future (for iOS 10.3 and future versions). Owners of 32-bit devices with iOS 10 support can also save blobs in .shsh format in any way you choose.
Rollback to 10.2.1 from a later version
Who should do this?
Any user of firmware is newer than 10.2.1 should be rolled back immediately to increase the chances of jailbreaking. In general, the lower your version of iOS, the greater the likelihood of a successful jailbreak.
Upgrade to 10.2.1 from an earlier version
Who should do this?
To nobody. This is madness!
Do not miss the moment!
Remember that signing iOS 10.2.1 may end very soon. After this, you will no longer be able to save blobs or return to iOS 10.2.1. If a jailbreak for iOS 10.2.1 is released in the coming months (which is unlikely, but possible), you may need to downgrade to that version from iOS 10.3+ - which is why you need to save the blobs now. Those running beta versions of iOS 10.3 will need to downgrade immediately to do so.
Remember that although this may not looknecessary due to the lack of jailbreak for iOS 10.2.1, this is a good reserve for the future. If you do not save blobs now, you may regret it later. Good luck