The handling of the Stormy Daniels payoff is the violation of election law. That is not what he is charged with. He is charge with falsifying documents to cover up that violation. When documents were issued is irrelevant. It makes no different when documents were issued.
The evidence of violation of election law will not be presented till the trial so we have to wait for that but I don't think that is going be the problem for the DA. I think it is going to be tuff proving that Trump sighed the documents with intent to cover up the election law violation.