I must agree with davegurn tho; its difficult to understand how someone could have jail broke and unlocked their phone without realising you can't just update it like that. Everything about JB says its specific to a particular firmware. And all the jailbreak tools make it very clear you will lose your unlock if you update. It's in big capital letters everywhere the subject is discussed.
I can only think the OP bought the phone already jail broke and unlocked, or got someone else to do it for them.
I gave my brother in law detailed instructions on jail breaking and SHSH blobs and root password , iFile, etc. He was like "ah that sounds complicated can you not just do it for me?" I said I would, but you NEED to know this stuff. I think a lot of people just think jailbreaking is just a way to get free AppStore apps. Before I jailbroke I read around it for about a week to be sure I knew what I needed. Even then I didn't know about SHSH blobs till later.
Again, not having a go at the OP. it's just always worth finding out about stuff even if you don't think you need it.