Avoiding update to 5.6.1 on PW2

Hello, I have a newer PW 2 with the FW version 5.4.5.1 installed. I reupdated it after downgrading and jailbreaking. Now I have heard that the update 5.6.1 is very scary so i am trying to avoid it. I have had the kindle on airplane mode since then, but I would like to still use the WiFi.

So just wondering if this method explained by ricky1989 protects from the 5.6.1 upgrade...? Or should I use the BackdoorLock?

http://www.mobileread.com/forums/sho...d.php?t=219986


Does anybody have experience with that yet? Thanks.