Broadvoice Inc Changed 2 yr customer's plan due to 'possible abuse'; agreed to change it back, then reneged Billerica, Massachusetts

I've had the Unlimited World Plus Plan for almost 2 years. Received an email indicating possible abuse from them and that they had changed my plan due to more than normal activity. I explained that my wife makes international calls to her family regularly (as she's done for almost 2 years thru Broadvoice) and was recently out of the country visiting them for about 6 weeks. I asked them to compare current activity to activity prior to March. They did and agreed to restore my plan on the phone, but later sent another email saying I'd have to agree to some terms before they restore my service. I agreed to continue to pay for the service I've had since Oct '08, but didn't agree to their new plan. So, they charged my credit card about $70 (in addition to the $42 monthly payment already charged 2 weeks ago). I filed a dispute yesterday with my credit card provider.