I'm not sure about this, but I know that many problems with towers that have already been upgraded is the lack of back haul. With the amount of microwave back haul being implemented, when the fiber optic back haul is late, it can affect up to 6-8 towers. Forcing Sprint to continue to use the legacy back haul and only 3G. It is difficult to accept when you expect to see vast improvement, but it won't be long until there is a premium network fully implemented.
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