From what I've read, that's not true. The ballots coming back were going to be checked against their "Special List" of approved voters (by their standards), and if a single ballot didn't match, they were going to toss the entire batch, which could be as many as 10,000 ballots. It would mean losing a lot of MAGA ballots, too, but if you concentrate the rejections on the Blue states, it will have an impact on Dems.

They have interference plans for Before, During, and After the election, and they are still going to interfere with the returning ballots in some way. They don't expect ALL their plans to work, but enough could get through to make a difference. We have to remain vigilant, and knock down each challenge as it comes.