The latest software update from Apple will patch several exploits currently used to Jailbreak all iOS6 devices. In order to hold on to your Jailbreak and be able to downgrade back to 6.1.2 you should back up your SHSH Blobs to your computer using TinyUmbrella. Below is a full tutorial on saving your SHSH blobs essentially making you future proof for the time being. So long as you dont click that big red Update button on your device. You dont need to know what these do at the moment, you just need to have them. Trust us.
Text Tut:
Step 1: Download TinyUmbrella v6.12.00. [Download links: [ Register or Signin to view external links. ] , [ Register or Signin to view external links. ] ]

Step 2: Save the downloaded file on your desktop and double click on the app icon to run it.

Step 3: Connect your device to a PC or Mac using USB.

Step 4: In the left-hand corner of the TinyUmbrella window, select your device under Connected Devices.

Step 5: Click on the Advanced tab and then uncheck the following:

- Save ALL Available SHSH

- Request SHSH From Cydia

Step 6: Now change the Save SHSH Directory to a folder named SHSH and select somewhere like Desktop or My Documents.

Step 7: Click on the log tab to preview the status of the entire process.

Step 8: Select your device in the left column and click on the Save SHSH button in the right-hand side of the window. TinyUmbrella will save the SHSH blobs for iOS 6.1.2 to the folder that was selected in Step 6.

Step 9: Open the SHSH folder on your desktop (or wherever you placed it) to verify that the blobs are perfectly saved.

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These files will come in handy later on once Apple releases 6.1.3 and Evasion no longer works as a Jailbreak, However fear not Evaders have already said they wont be giving up on this. As soon as the new update drops they will be hard at work finding the next set of loopholes to use. Unfortunately this seems to be the endless cycle of cat and mouse with Apple. You would think after all these years they would support it officially.