I am happy to say that I won my personal war against at&t. It's a long and painful story which involves talking to 10+ at&t representatives including 2 supervisors in 4 or 5 different departments, including the Retention department (what is Retention? Think about it. It's customer retention. Last resort central. They could not help either, by the way). Maybe I'll tell it someday. Suffice it to say, I GOT WHAT I WANTED.
Lesson? Keep bothering them. Argue. Threaten to cancel. You will eventually come out on top.