iPhone 4s iOs 6 data usage problems on Verizon

Last night around 6PM I lifted the usage controls on my teenage cousin's iphone 4s. We had never set a data limit for the phone because she only uses it for internet when at home on the wifi network. We only had it on her phone to be able to block unwanted numbers, but the feature also allows customers to set data caps, internet restrictions by age ect.

Prior to last night her usuage was minimal. However, within 6 hrs of the usuage control being lifted suddenly I was notified we'd hit 50% of our 6g data plan. In the morning when I woke up I had a text saying we'd hit 75% of our usage plan. I logged into Verizon and it indicated she had consumed 4.6g.

I spoke with Verizon and the first reprepresenative told me that this was a known iOs 6 issue for iphones and asked me to check if the phone was using the that operating system. She said if it was Verizon would be giving credits to customers because it was a known issue. I hung up, called my aunt and learned that in fact iOs 6 was installed. She also confirmed that the phone settings had not changed. It was still only using wifi. Verizon data usage remained turned off.

I called Verizon back and spoke with a second representative who then told me that it was not an iOs 6 issue, but just an iPhone 5 issue. She said the previous information given to me was incorrect; it was hardware and not operating system based problem. I then reapplied usage controls and went in to set a data limit, for the first time, and discovered that the iPhone's data usage had now reached 5.4g of 6g. I still have 18 days left on my billing cycle and just .6g of data remaining. It seems crazy to me that I should have to set a cap on data usage for a phone using wifi to prevent that phone from maxing out verizon data, but that is what I have done until I can get to the bottom of this

The rep told me to visit Apple for further details. I also googled it and found stories on CNN and TheNextWeb reporting instances where individuals with the iOs 6 on iphone 4s were also experiencing problems, but nothing concrete on how to resolve it.

Can someone please clarify for me what is going on or where I can find a solution to this.

Thank you in advance.