Iphone 4 restore to 5.1.1

Hi iClarified, I have iPhone 4 on 4.0.2. jailbroken and unlocked with ultrasn0w (BB 01.59.00) Now I want to restore to newer iOS 5.1.1. (later when it will be possible to 6.0), now I have question can I use the new redsn0w (redsn0w 0.9.15b2) to restore and preserve baseband and later to jailbreak it and unlock it with ultras0w?? Thanks in advance….