Ok, let me get this straight. As of today at 2:20 am EST, Apple is signing 5.0.2 software, again.
Last friday I was trying to jb a friend's ATV2 that was on 4.4.4. but had 3194 error on iTunes. That's when I found out that Apple wasn't signing anymore 5.0.2, hence the error.
I tried many methods. Saving blobs, weird workarounds, and suddenly I had an ATV2 stuck in DFU mode and had to update to 5.1. I still tried to go back to 4.4.4 with my saved blobs and never worked. 3 complete frustation days.
Then the miracle happened. While reading this thread http://forum.firecore.com/topic/8977 I realized that this user was certain that Apple was signing 5.0.2. I even replied that his proccedure was wrong because that couldn't be possible. Posts later, someone wrote that he read in Apple forums that because of many issues with 5.1 on ATV3, Apple had no choice than having to re-enable the signing of 5.0.2, so this ATV3 users could downgrade.
So, with this 5.1 ATV2, I was able to downgrade in iTunes to an official 5.0.2 ipsw, then, once back in 5.0.2, I fired up season pass and let the magic begins. Now I have a jailbroken ATV2 who used to be 4.4.4, then 5.1 and then back to jb 5.0.2.
Ok, yes, I'm happy. so I suggest that if you accidentally updated to 5.1, NOW is time to go back, or save your blobs. Don't know when Apple kills the 5.0.2 signing again.