Is iOS 8.1.1 downgrading possible? Let's observe this question. On December the 1st Apple company has stopped to sign the iOS 8.1 firmware. It means only one thing that from now you have no chance to downgrade from iOS 8.1.1 and also jailbreak. But it is great that TaiG jailbreak is compatible with iOS 8.1.1 update. You should better upgrade and then jailbreak your devise.
Additionally TaiG jailbreak works with the latest, unreleased iOS 8.2 beta for iPhone, iPad and iPod touch.
MuscleNerd famous jailbreaker guaranteed that the TaiG jailbreak is safe for usage. It is better to upgrade and then jailbreak using TaiG tool, if your device is not on iOS 8.1.1. As it is always better to be on the latest firmware on compatible devices.
The TaiG jailbreak gains iOS 8.2 beta support, but for the resent time with that firmware it just shows errors. It can so that Apple has patched all the exploit in iOS 8.2 beta. Or most evidently is that the TaiG team is waiting for Apple's iOS 8.2 public release. And just after that it will add support for iOS 8.2.
Until recently, if you by mistake upgraded to iOS 8.1.1 and accidently lost your jailbreak, you could downgrade to iOS 8.1 as Apple was still signing iOS 8.1 firmware. On the 1-st of December it came to an end. And if you ask is iOS 8.1.1 downgrading possible? No. If you somehow stuck on iOS 8.1, you’ll need to upgrade directly to 8.1.1. And in case you want to jailbreak your device, you could do it with the help of TaiG iOS 8.1.1 jailbreak.