Verizon Wireless will soon begin forcing grandfathered unlimited data customers to switch over to a tiered plan if they use over 100GB in a single month. And if those customers are unwilling to move to a newer plan by August 31st, they'll be disconnected from the network completely.

Yesterday, Droid Life reported on the carrier's plan to cut off service for users who regularly burn through extraordinary amounts of data each month. As a longtime unlimited data customer, the news had me a little nervous — especially since at the time, it wasn't clear exactly how much data usage Verizon would deem to be excessive. If it were something like 30GB, I'd be in trouble. Now the figure is official. Well, sort of. All we know is that it's somewhere over 100 gigabytes. Ars Technica confirmed the limit with Verizon directly.

"Because our network is a shared resource and we need to ensure all customers have a great mobile experience with Verizon, we are notifying a very small group of customers on unlimited plans who use an extraordinary amount of data that they must move to one of the new Verizon Plans by August 31st," a spokesperson told Ars. "These users are using data amounts well in excess of our largest plan size (100GB). While the Verizon Plan at 100GB is designed to be shared across multiple users, each line receiving notification to move to the new Verizon Plan is using well in excess of that on a single device."

That 100GB plan, by the way, costs $450 per month, far more than the $49.99 data charge now being paid by those of us clinging to our unlimited lines. Verizon claims that under 1 percent of customers remain on unlimited data plans. And within that bunch, most people (myself included) are at this point firmly out-of-contract and paying for wireless service month to month.