I believe the estimated guess is sept. It's really hard to say. They have made quite a few revision builds of the beta in the past month. So while they are getting closer each carrier will be different. The carriers have to test each revision on all of their models to see if it is relatively bug free. If not the bugs are reported, fixed, and a new revision built. Then they test it and so on until a revision is found to be relatively bug free. Then it gets released.
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