Subscribers are already beginning to receive AT&T's promised warning messages for throttling download speeds
on the top 5% of its data users. One Reddit member nicknamed skelatwork
has posted a screenshot of its own warning message, which was received when he went a little over 11GB of usage for the month.
It's interesting that a week ago skelatwork writes how he got a text too, and switched to PDAnet, which allows you to hide usage from the carrier's counters. Since the date on the message he posted is from yesterday, we assume that's another warning now.
In June, AT&T announced that it will be throttling speeds for the heaviest 5% of its data users, since they are skewing the network usage for the rest quite a bit:
October 1 is tomorrow, so it will be interesting to see reports from people who got this AT&T message whether their download speeds have been throttled, or the promised grace period enacted.