Following the release of iOS 9.0.2, OS X 10.11 El Capitan and iOS 9.1 beta 3 for both developers and public beta testers, Apple has initially stopped signing in the older iOS IPSW firmwares, and has now closed the window of iOS 8.4.1 for all iPhone, iPad and iPod touch devices. Makes users can no longer upgrade or downgrade to those versions of iOS using iTunes.
Not only has Apple closed the signing window of 8.4.1, but also targets for iOS 9.0 which was released only about two weeks ago. Reason? It could be like being aware of jailbreak exploit threat, or else, never done like this before. Why that? If it stops signing 9.0, it can stop hackers to dig into its firmware to find any loop wholes, and just like that every time it releases new version of iOS update and stop the previous, it can force users to upgrade to the latest and greatest without any doubt. How clever, isn’t it?
Finally, the signing window of 9.0 through currently appears to be shut down only for the latest iPhone 6s and iPhone 6s Plus, but it wouldn’t be too long now before they close it for all other devices as well. Guess what, iOS 9.0.1 is still being signed and what for?
Big deal here is what? Closing of signing window for 8.4.1 and 9.0 means you can no longer downgrade your iOS device to the older firmware versions. For jailbreakers, this could be strange, because apparently there is a jailbreak in the works for iOS 8.4.1 which is rumored to be nearing release. Now, Apple has stopped siging it, closed all the windows making eveyone who hasn’t downgraded to 8.4.1 from any version of iOS 9.x can no longer or never be able to downgrade or jailbreak on iOS 8.4.x, if or when the untethered JB is made available.
Good news for those who are still running their iPhone, iPad or iPod touch on iOS 8.4.1. Care about jailbreak, then, sit tight and wait for the jailbreak release.
You can download iOS 9.0.2 from here: Download iOS 9.0.2 Links For iPhone, iPad, iPod touch [IPSW].