I have been out of the know for a little while and thought the other day I had solved my issue, but turns out I just came up with more questions. I currently have an iPhone 3GS Unlocked and Jailbroken on 3.1.3 (7e18) I have baseband version 5.12.01 and I do not know how to check the bootrom if it needs to be changed. I was thinking the best way was going to be upgrade to a 4.2.1 custom firmware created with pwnage tool and using Tiny Umbrella as the SHSH BLOB server. Is there anything I am missing? I don't want to be left phoneless incase of a crash or something. I am currently using the phone with TMobile. Any other info needed just let me know. I just want to make sure I am in the clear to go ahead and do it?