Is Apple still signing 6.1.3 for iphone 4?

Question

Hello,
Something like one month ago i decided to go from 6.0.something to 6.1.3 because my iphone 4 was running too slowly.
At first i thought about restoring but i got lazy, and thought i would just update through itunes, since itunes always tries to make you update.
So i ended up with 6.1.3. My iphone was working a bit better concerning the speed, which i was happy with, however, i saw a huge difference regarding the battery.
Before i could use my phone the whole day, phoning, browsing the net, listening to music, etc etc.... battery wasn't amazing but i definitly could rely on it for the whole day.
I never had any push of any kind, location services were turned off when not needed, brightness manually set to a low percentage, etc...
Since i updated to 6.1.3, and took the time to set up the iphone the same as it was before (i updated and set up as a new iphone), the battery life is a complete nightmare.
Its not about loosing 10% percent capacity or so, the battery is now emptying when not even doing anything.
I tried everything i could find, i'm 99 percent sure this is not a setting issue (spotlight is even turned off...), and even though i don't want to mesure how much of a decrease i'm witnessing, i guarantee the difference is amazing.
I'm thinking this is a deliberate way into making me think i should get a new iphone, which i don't want to.
I used to have an iphone 4 running Ios 4 and working really fast with great battery, never updated, but then something went wrong with its hardware and i HAD to let apple exchange it for a new iphone, which was great but i ended up with an up to date phone (6.something), it was a bit slower, battery was not as good but it was acceptable.
Since i updated it's a disaster.
I think there might be a small chance my update went wrong somewhere, and would like to try and restoring it to 6.1.3, but i don't know if apple is still signing it.... i don't wanna hit restore with the option key, select the 6.1.3 firmware, have my phone emptied and then itunes saying this is not possible, directly forcing me to get ios7.
I also believe i virtually have no chance to downgrade to earlier than 6.1.3, which is a shame, cause it worked so much better back then....and no i'm not interested into jailbreaking, did that years ago with a 3gs and found it uninteristing.
So can i restore to the same firmware through itunes?
If i can and nothing changes, then i'll go with 7, since i don't see how it could be even worse (maybe even slower....)...
And if there is no solution, then maybe i'll find a rope....!
Thank you in advance

Answer 1

No you can't downgrade and it is not supported by Apple, so you either need to live with what you have now and not upgrade again or go for iOS 7 and see what happens.
I have only just updated my phone to iOS 7 this morning and had no problems - did it via iTunes 11.1 and the whole process took about 20 mins with a good fast internet connection.  No problems so far and I actually quite like the new look of iOS 7.