OSRestoreX
How to restore iOS 10.2 via OSRestoreX without losing jailbreak

Jay Freeman's Cydia Eraser is still being developed to support compatibility with the latest iOS 10 firmware versions while third-party jailbreak app developers have been consistently contributing to help the user community in their quest to preserve the jailbreaking capability of an iOS device.

Those who are experiencing unexpected problems with the installed jailbreak may go ahead and try restoring their device back to iOS 10.2 using the OSRestoreX tool without losing jailbreak capability. The best part of this method is it allows you to revert back to an older firmware without actually updating your device to the latest iOS version.

Note: As this method involves restoring a fresh or clean version of the firmware, it is absolutely necessary to backup your important data and settings on the phone as the process will erase all stored content.

Step 1: Assuming that you have already backed up user data and settings on the device, you can go ahead and launch the Cydia installer app.

Step 2: Wait until the Cydia app launches and refreshes itself, then go to Sources > Edit and tap the Add button. Add the following repo URL: http://coolstar.org/publicrepo and then hit Add source.

Step 3: Once again go to Sources > Edit and add the following repo URL: http://repo.jailbreakhub.org

Step 4: Open the Search functionality in Cydia and look for the package named 'Stashing'. Once you find it, just double-check to confirm if it supports iOS 9.2 through iOS 10.2 and then install it.

Step 5: Navigate to Sources section and select the recently added jailbreakhub source and then tap on All Packages. Now, scroll down and locate the package named 'OSRestoreX'. Install the restore tool and it should automatically start erasing all stored data.

Step 6: Wait until the file erasing process completes and then you will notice red and yellow text appear on screen before crashing Cydia. This means the Cydia app has been erased although its app icon should still be visible on Home screen.

Step 7: Open Settings app, go to General > Reset > Erase All Content and Settings. Then choose Erase iPhone and then select Erase iPhone again to confirm the action.

Step 8: You will now be redirected to the stock iPhone setup screen. Just follow the onscreen instructions and you should be able to regain your previously jailbroken iOS firmware in its stock or factory settings. You can now rejailbreak your firmware to enjoy the benefits of a jailbroken hardware.

[Source: Redmond Pie]