AT&T’s stance on unlimited data is once again in the spotlight as a new wave of smartphone users cry foul over the carrier’s questionable policies. The nation’s No.2 carrier does not currently offer an unlimited data plan to its smartphone subscribers. Instead, there are three available data plans that include “soft” caps, allowing subscribers to continue using data services for additional fees after the soft cap is reached in a billing period. Users who have been with AT&T since before the carrier switched to tiered data plans — loyal customers who have in some cases maintained the same account in good standing for more than a decade — had the option to retain their unlimited data plans when AT&T first made the move to tiered plans. While heavy users were initially relieved when the opportunity to retain their old unlimited plans presented itself, that relief has quickly turned to disdain. Read on for more.

AT&T announced last summer that it planned to throttle unlimited smartphone data users beginning in October. The carrier said that the move would only affect the top 5% of heavy users, and it was a necessary measure in order to “manage exploding demand for mobile data.” The new policy meant that unlimited data users could continue using their handsets without data limits, but heavy users would see their data speeds reduced at a certain point each month if they used too much data. AT&T took particular care in not setting a specific limit that would have to be reached before throttling kicked in, but most typical users presumed it would be a number they would never hit.

When October came around, AT&T’s new policy took effect. That very same month, BGR began receiving tips from AT&T subscribers who received notices by SMS that they were nearing their monthly limits and that data speeds would soon be reduced. The peculiar thing, however, was that these subscribers hadn’t even used 2GB before receiving the notices; 2GB was the same amount of data afforded by AT&T’s top tiered data plan at the time.

Since October, there have been countless accounts of similar happenings. AT&T users in regions across the country are notified with the following SMS message that they are about to be throttled: “Your data usage this month places you in the top 5% of users. Use Wi-Fi to help avoid reduced speeds.”

What is most interesting about this new wave of complaints, however, is that subscribers are still getting notices that they are in danger of experiencing reduced data speeds as they approach just 2GB of usage in a single billing period. As of January 22nd, however, AT&T’s main smartphone data plan offers 3GB of data for $30 per month — the same fee unlimited data users are paying for their plans. BGR has even received an email from an angry unlimited data subscriber who received a notice after using just 1.6GB of data during a billing period.

As it stands today, a user with AT&T’s $30 tiered plan can enjoy about 50% more data than an unlimited data user. Enjoy is the key word, because throttling brings AT&T’s typically speedy 3G and 4G data speeds down to 2G territory.

Last paragraph updated to remove reference to an earlier study conducted by Diffraction Analysis, which was cited incorrectly.