Apple has stopped signing iOS 9.0.2 ie; Downgrade is not Possible

Apple has stopped signing iOS 9.0.2 firmware file for
iPhone, iPad, and iPod touch just over a week after releasing iOS 9.1. Apple
is now only signing iOS 9.1 upon restore. This means that you
basically are forced to upgrade to iOS 9.1 in all situation.
This
means that users won’t be able to downgrade from iOS 9.1 to iOS 9.0.2 and jailbreak your device. You can see the signing status for firmware files just by
visiting ipsw.me.

Note: Jailbreakers must be very careful
while installing jailbreak tweaks as
a bad tweak crashes your iPhone and force you to restore your device & lose
your jailbreak. So. if you want to restore your
device, you can always use Cydia Impactor, a tool that lets you restore iOS and
remain on the same firmware and for this your device need to be jailbroken.

So Stay updated for iOS 9.1 jailbreak.