When AT&T throttles the data speeds of its customers who have “unlimited” data plans, it really means business. Ars Technica reports that AT&T “unlimited” data customers can’t stop AT&T from throttling them even if they turn off their phones’ LTE radios and try to get their data solely from the carrier’s HSPA+ network.

RELATED: New report rips a hole in AT&T’s justification for throttling its ‘unlimited’ data customers

AT&T customer Andy Abreu tells Ars that his connection speed used to dramatically slow after he hit 5GB each month despite the fact that he had a supposedly “unlimited” LTE data plan. Abreu tried switching off his phone’s LTE radio and even swapping his SIM card into a device that only had HSPA+ connectivity but it didn’t seem to matter — he was still getting throttled.

What makes this particularly galling is that Ars found last week that AT&T throttles users’ LTE data once they reach their 5GB limit at all times, regardless of whether or not there’s network congestion. AT&T typically uses network congestion as an excuse for throttling “unlimited” data customers, but this justification makes no sense if the carrier is doing it at all times of the day.

Be sure to read Ars‘ full report on AT&T’s amazing throttling powers by clicking the source link below.