For example, if an unlimited data plan subscriber uses about 3GB of data per month, he'd have to pay $70 plus $40 for a total of $110 a month. With his unlimited plan he'd pay $30 a month for data and $50 for voice and text service. His bill could go up about $30 a month if he moved to the new plan. If he used 4GB of data per month, the difference in price would be $40 a month.
But it's not just heavy data users with unlimited plans that lose out with these plans. Some individual subscribers on the tiered plans will also suffer, because they will effectively be paying about $20 more a month for a comparable service.