They can't even get their meters right for that. I started out a month with like 4GB because I used about 25 the month previous. I stopped using data heavily several days before.
(I sync'd and unsync'd my spotify playlists just to get my usage up; they sent me a text that month explaining that if I went over 3GB again in any future billing cycle, I would be throttled. I usually am around 1.5-2.5GB/month... I was traveling. Makes me so annoyed. If they would have said they'd throttle me if I went over 3GB in the next 3 billing cycles, I wouldn't have cared.