Currently, those Boost and Virgin subscribers that exceed the data cap have their data speed throttled to 256Kbps. The 2G speeds that throttled customers will have starting on May 6th, are slower. Sprint says that only a small percentage of Boost Mobile and Virgin Mobile customers exceed the cap. Those that do can top up their account early to restore the faster 3G/4G data speeds.
How will I know if my data speeds have been reduced?
If you are close to reaching 2.5GB of data in a month, you will receive a text message alerting you. Once you reach the 2.5GB limit, you will receive a text message letting you know your data speeds will be reduced for the rest of your plan month. You can check how much data you’ve used at any time during the month by logging into My Account and checking Data & Web history.
By putting this data speed reduction in place, we’re making sure we can deliver the same quality of service to all of our nationwide customers – we appreciate your understanding at this time."-Sprint message to Boost Mobile and Virgin Mobile customers
source: PhoneNews, WirelessWeek via AndroidGuys