Is an unlimited data plan still unlimited if there’s a threshold marking the point at which your network speeds will be slowed down? Sprint seems to think so: after telling customers in June that it would no longer throttle speeds for customers on its unlimited plan using an excessive amount of data, today Sprint has changed its tune, and says it’ll slow down customers when they reach a 23GB monthly threshold.

In the name of network management, Sprint announced that as of today, Oct. 16, it’s introducing a new “Quality of Service” practice that applies to customers who choose an unlimited data handset plan (either new or plan upgrades) from here on out.

“For these customers, if they use more than 23GB of data during a billing cycle, they will be prioritized on the network below other customers for the remainder of their billing cycle, only in times and locations where the network is constrained,” writes Dr. John Saw, Sprint’s chief technology officer. Unlimited data customers will not be charged overage fees even if they do hit that 23GB monthly mark, however.

It won’t be easy to gobble up that much data — CNET points out it’s equivalent to streaming all five seasons of Game of Thrones — as Sprint says this change is aimed at a “small minority” of customers who “might occupy an unreasonable share of network resources.”

This is a reversal from Sprint’s decision in June to cease throttling unlimited data customers — right around the time net neutrality went into effect. That rule classifies Sprint as a common carrier under Title II and as such, it is not allowed to muck around with customers’ connections — no slowing down, blocking or otherwise choking.

But it is something other carriers have done as well: T-Mobile also slows down users who hit a 23GB threshold, while AT&T has gotten itself in trouble with the Federal Trade Commission for peddling an unlimited plan but throttling folks at only 3GB.

Sprint itself points to this 23GB threshold as “standard in the industry,” adding, “We agree this is a smart approach towards making sure a small number of customers don’t adversely impact the experience for others.”

It might make wireless customers cranky when they’re subject to throttling, but if it’s necessary, mobile companies are indeed allowed to do it. Network management is a real and legitimate thing.

In the meantime, if you’re not binge-watching Jon Snow’s curly locks whipping around in the wintry air everywhere you go, you should be okay: Sprint says notes that about 3% of its postpaid subscribers are “using overwhelmingly disproportionate network resources,” and that its goal with the policy change is to prevent some of those folks from “negatively impacting the other 97 percent of customers.

It remains to be seen whether the Federal Communications Commission or the FTC will go after other carriers, including Sprint, for instituting throttling thresholds on plans that are supposed to include limitless data.

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