Hey guys, I've finally decided to upgrade my unlocked & jailbroken iPhone 3GS running 3.1.2 to iOS 4.0/4.0.1. How do I go about this? Should I first mod the iOS4 ipsw using pwnagetool and then use jailbreakme & Ultrasn0w ? I bought my iPhone off eBay and it came unlocked & jailbroken with Rock so I'm not sure about the SHSH blobs. Is it necessary to have them saved and can I save them using Tinyumbrella ? I'm running baseband 05.11.07 if it helps. Thanks in advance!