This is a discussion on Possible to Downgrade 5.1.1 to 5.1 on iPhone4? within the iOS 5.X.X forums, part of the iOS Forum category; By Mistake I upgraded to 5.1.1 on my ipHone4 and baseband 4.12.
Is it possible to downgrade to 5.0.1....
By Mistake I upgraded to 5.1.1 on my ipHone4 and baseband 4.12.
Is it possible to downgrade to 5.0.1.
Why do you want to downgrade to 5.0.1?
If you rely on an unlock.....then your out of luck...downgrading to 5.0.1 is possible only if you saved SHSH blobs....but downgrading the baseband is not possible.
So even if you did downgrade to 5.0.1 your baseband will remain the same....as it is not possible to downgrade baseband no matter what.