Hey guys. Since im a developer i have access to the 4.0 beta.. i would really like to try it out but would i lock myself out of 3.1.2? I have my SHSH keys for 3.1, 3.1.2 and 3.1.3 so thats not any problem. The only thing im worried about is that i once helped my uncle with his iPhone 3G and he was unable to downgrade because of a newer baseband. So if i upgrade to 4.0... would i then by any chance lose 3.1.2 compatability?