downgrade baseband 6.15.00 to 5.13.04
MuscleNerd, in tweet, hints that they are working on downgrade baseband 6.15.00 to 5.13.04. In a reply to one of his followers, Musclenerd says that they are working on downgrade iPhone 3GS baseband 6.15.00 to 5.13.04 rather than an unlock for baseband 06.15.02, 05.14.02, or 05.15.04.
Someone asked MuscleNerd in a tweet; “what about people with 3GS firmware4.3.1 and baseband 5.16.02? How long do we have to wait to unlock our devices 
i hope soon”. MuscleNerd responded in two tweets:
for those at 05.14, 05.15 or 05.16 I really don’t see an unlock coming. Rather, it’ll be: update to06.15, then down to 05.13
(because the downgrade from 06.15 goal is much higher priority than explicit 05.14,05.15, or 05.16 unlock. Achieves same.)
So the idea is, there won’t be an unlock for iPhone 3GS baseband 5.16.02, 05.14.02, or 5.15.04.Rather, dev-team is working on a method by following which, users with iPhone baseband 5.16.02, 5.14.02, or 5.15.04 will update their baseband to iPad baseband 6.15.00 and then downgrade baseband 6.15.00 to an iPhone unlockable baseband 05.13.04.
