I'm currently on iOS 6.1.1, but due to many crashes and volume issues I've decided to restore my iPhone 4S. I'd like to upgrade to iOS 6.1.2 if possible without going to iOS 6.1.3, since that update patches the evasi0n jailbreak. Is this possible? If not, I do have a 6.1.1 SHSH file saved from TinyUmbrella, is there a tutorial I could follow to restore right back to iOS 6.1.1 using that SHSH file? Thank you!