I don't know about back dating one way or the other.
I do know that it doesn't matter in this case because the whistleblower used the old form that had been in place since May 2018.
Despite all of the innuendo I haven't seen Davis or any Comgresspeople dispute this.
Davis does dispute the claim that First hand knowledge is not required to be a whistleblower by providing this link I posted in Post #43 above.
RE: the whistleblower used the old form that had been in place since May 2018.
Well, if he did, and as Davis reported, the form was adjusted to make it compatible with an existing requirement, all Atkinson had to do is tell the Republicans, “I simply made an adjustment to the May 2018 form to make it reflect the original law.” or something to that effect. Did he?