A while back, we reported that AT&T had stopped throttling unlimited data users except in cases when the network is congested.

We were wrong. AT&T did change its policy to stop the automatic throttling of many unlimited data plans, but the company’s older, more draconian throttling policy still applies to customers with unlimited LTE data. AT&T told Ars the policy will be changed for all customers sometime in 2015, but it did not say whether that will happen closer to the beginning of the year or the end of the year.

Here’s how it works: Customers who have 3G or non-LTE 4G phones and “legacy unlimited data plans” are throttled for the remainder of the billing period after they exceed 3GB of data in a month, but only “at times and in areas that are experiencing network congestion.” 4G and LTE are practically synonymous these days, but AT&T also applies the 4G label to its HSPA+ network technology.

4G LTE customers with unlimited plans aren’t throttled until they reach 5GB of data. However, these customers are throttled for the remainder of the month at all times of the day and night regardless of whether the network is congested.

Put simply, we misread AT&T’s policy, assuming that the new, less strict throttling policy applied to all 4G users, including those with LTE phones. AT&T customer Julian Benton of Santa Rosa, California, whose iPhone 6 is being throttled right now, alerted us to what’s actually going on.

Benton started getting throttled on November 19 or earlier, with cellular speeds reduced from 23.51Mbps to just 0.11Mbps. Since then, his speeds have remained steady at around half a megabit per second. Benton’s billing cycle extends until December 9, so he has a few more days to go before his speeds are restored.

Julian Benton

Julian Benton

Julian Benton

AT&T’s motive is obvious—it’s all about money

AT&T’s goal is moving customers off unlimited data plans and onto plans that hit customers with automatic overage fees when they exceed data limits. More than 80 percent of AT&T postpaid smartphone customers are now on limited plans. Benton, who has had unlimited data since the second iPhone came out in 2008, pays about $195 a month for three lines, one used by his wife and another by his teenage daughter. The parents both have unlimited plans while the daughter gets 3GB a month.

Benton had been throttled in the past, but typically at the very end of a billing cycle. This time, he used an unusual amount of data because the Wi-Fi network connected to his 6Mbps DSL service was congested with his children home on vacation. “Sometimes Wi-Fi gets slow and I know there’s a cell tower two blocks from me,” he told Ars. “Without it being throttled, I get almost twice the speed off my cellular data downloads than I do off my Wi-Fi, especially when everyone is using it.”

Benton generally uses about 3GB a month. He runs a home inspection business and is often on the road and relying on GPS and Siri. In November, streaming video and music helped push him over the 5GB limit.

Benton said AT&T didn’t notify him when he hit the throttling point, but he called customer service and asked them to restore his speeds.

The customer service agent “said no one can turn [the throttling] off,” he said. The agent also advised him that he shouldn’t access streaming music and video except when he’s on Wi-Fi. In other words—don't use the data you're paying for.

“She explained to me the reason why it’s throttled is the system can’t handle it if I go over that [5GB limit]," Benton said. "I said, 'that’s interesting because you guys sent me an offer that if I go ahead and change my data plan I can have up to 15GB of downloads to share between my family. But if I use that as one person, apparently you’re not going to throttle me up to 15GB and even if I go over 15GB you don’t throttle me, you charge me more.' Clearly they’re trying to get people off [unlimited data] and at this point I’m ready to get off it, too."

Benton said he’s leaning toward buying the 15GB family plan that will cost about the same as what he pays for his family’s current plans. (That pricing may no longer be available now, since AT&T just ended a promotion.) For now, since he’s still being throttled, websites don’t always load, streaming music and video is off-limits, and he uses a GPS device that’s slower than Google Maps. “It’s a first-world problem,” he said. “Sometimes I ask Siri to do something and she says, ‘I’m sorry can’t do that right now,’ because she can’t download fast enough.”

Pressure from FCC hasn’t stopped most throttling

The Federal Trade Commission sued AT&T in October over its throttling policies.

Federal Communications Commission Chairman Tom Wheeler has also pressured carriers over throttling policies, arguing that customers who pay for unlimited data should not be slowed down unless there is a legitimate network management need for it. Verizon Wireless caved to the pressure and decided not to throttle 4G users, although it still throttles 3G ones in congested areas. Verizon's LTE relies on spectrum with open access requirements, which may be why the company conceded to Wheeler.

An AT&T spokesperson acknowledged that unlimited LTE plans are slowed after 5GB regardless of whether there is any network congestion. However, the company plans to change its system so that LTE users who hit that 5GB threshold will only be throttled in congested areas. That would give AT&T’s LTE users the same treatment as its 3G and HSPA+ users.

The distinction between 3G/HSPA+ and 4G LTE is expected to go away next year, the company said. “Once technologically available, we expect to adopt the same model for customers with 4G LTE smartphones on unlimited plans sometime in 2015,” AT&T told Ars.

If the switch were to happen in the next few months, Benton said he might be willing to wait. But since it could be more than a year, he’ll probably ditch his legacy unlimited plan. After that, he’ll be hit with overage charges instead of slower data when he goes over his limit—just as AT&T intended.

UPDATE: One AT&T customer who has also been throttled contacted Ars to let us know that the throttling continued even when he temporarily disabled his phone's LTE and switched to 3G. The customer switched to a limited plan to avoid the throttling.