You'll recall that back when AT&T and Verizon tried to kill unlimited data and shovel users onto metered plans--they "grandfathered" a select number of customers, letting them remain on the company's older, cheaper unlimited data plans. That said, AT&T routinely tried to do everything in its power to drive those users off those plans, including its 2012 gambit to block Apple's Facetime from working unless those users moved to metered plans, to lying when it was caught throttling users without informing them.
Those plans are notably less relevant since T-Mobile competition forced AT&T and Verizon to bring back unlimited data options. But some of those users remain on grandfathered unlimited data plans that are still better than AT&T's current offerings.
To help "solve" this, AT&T has slowly been raising rates on those users, and did so again this week. MacRumors noticed an announcement over at the AT&T website stating that the company's grandfathered unlimited data users will be seeing an increase from $40 to $45 per month for those lines, in the wake of a late 2016 hike from $35 to $40.
"Consumers are using mobile data at record levels and the trend is expected to continue," AT&T says of the hike. "To help make sure we continue to provide the best service for all of our customers, a small price increase is being made at this time."
"Customers who have a grandfathered $40 data plan will receive notifications of a $5 per month rate increase for the data plan," said AT&T. "The rate increase will take effect starting with the customer’s July, 2018 service."
Users on these grandfathered unlimited data lines will still see reduced speeds if they exceed 22GB of data in a billing cycle
and are in a congested area.