I understood that Barnes refused to talk on air until CBS came up with the records.
I frankly, think that the content of the memos is a big yawn. Those who thought they would swing the election are delusional. I listen to ABC radio and they are reporting hourly on this story. Each report repeats the allegation that Bush got preferential treatment. I don't thik they should keep repeating an unfounded allegation every hour, but they are.
That was the original story.
But the Washington Post revealed that Barnes called Rather "sometime during the Republican convention to volunteer his services" (probably on Sept 1).
A day or two later, on Sept 3, Mapes told her boss (Howard) she had the memos.