I am aiming for Funday/Sunday for releasing the downgrade from 06.15. but that's very much subject to possible delay.
14 June 2012
GPS Fix for 06.15.00 Soon to Be Released!
Update it has been released: True GPS and Baseband Downgrade Now available via Redsn0w: Click Here and to get setup and to get ready, click here. Musclenerd has successfully been able to downgrade a 3GS to baseband 05.13.04, it is also possible to downgrade to any baseband! This means 3GS users on Baseband 06.15.00 will have their GPS functionality restored. His latest tweets suggest that it will be incorporated into other click and play mac / pc tools such as Redsn0w. This will also work for 3G users.
The most encouraging tweet from MuscleNerd has been this one:
Hold on guys, stay subscribed. Will make a video and tutorial as soon as it is released, along with downloads :)