iOS 5.1 Beta (build 9B5117b) Updates iPhone 4S GSM Baseband to 1.2.01-1 from 1.0.13

By now, you should have already read in many tech blogs that iOS 5.1 beta has now been seeded to developers. For unlockers like us, we’re more concern of the baseband.

We can confirm that the iPhone 4S baseband has been updated to 1.2.01-1, up from 1.0.13 on iOS 5.0.1. The baseband version this time is rather interesting as it comes with a ‘-’ followed by a revision number.
As soon as we have the information for iPhone 4 and 3GS we will update this article. So, to summarize the baseband revision for iOS 5.1 beta:

• iPhone 4S: 1.2.01-1
• iPhone 4 (GSM): TBA
• iPhone 4 (CDMA): TBA
• iPhone 3GS: TBA

Looks like there’s still no latest news on unlocking iPhone 4 on baseband 4.11.08, although the most promising one is the Vold Miracle. However, even if this product does exist, most likely it won’t be released until iOS 5.1 is available to public.
Thank you to those who have emailed us asking how to unlock iPhone 4 on baseband 4.11.08 but really there’s no method of unlocking it except by replacing the baseband and NOR chips (which we had to stop due to high demands and lack of chips availability unfortunately!).

courtesy beihingiphonerepair