Just to be clear, Apple has just stopped signing iOS 8.1 which means people who are on iOS 8.1.1 will not be able to downgrade back to iOS 8.1 as Apple no longer signing iOS 8.1 firmware file. This was useful for jailbreakers, as you could downgrade back to iOS 8.1, and re-jailbreak your device using Pangu.
Unfortunately it will be no longer possible to downgrade to iOS 8.1 from iOS 8.1.1 as Apple has just stopped signing iOS 8.1 file. This was confirmed by Callum Jones, who runs the ipsw.me site, that provides real-time signing status for iOS firmwarefiles.
Green tick indicates that Apple is still signing the firmware file, whereas red warning indicates Apple has stopped signing iOS 8.1
However, people on iOS 8.1.1 can still jailbreak their devices using TaiG untethered jailbreak especially after MuscleNerd vouched for TaiG iOS 8.1.1 jailbreak.
You can follow our guide posted here on how to jailbreak your iPhone running on iOS 8.1.1 using TaiG jailbreak.
