Are you asking if you drop your data plan and just surf using WiFi will you get charged for data? If that's the question, then I would assume the answer would be no. Also. If you turn your radio off and surfed WiFi, I can't imagine you'd get charged some additional fee...
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Ah I see, well I would assume that if you had your network enabled while downloading, there's a chance that whatever you downloaded casme thru your data connection, not your WiFi connection. However, there is a 5gb monthly data allowance on BIS data plans, what did you DL?? Must have been pretty huge files to rack up that much data, were you tethered?
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