Who leaked John Bolton's draft manuscript to The New York Times?

Let me get this straight. So John Bolton, former Trump national security adviser, and his publishers sent a draft manuscript of his forthcoming book to the National Security Council for vetting purposes, to make sure he had not inadvertently included classified information in his account of his time serving in the Trump administration. And the draft was leaked to The New York Times! One copy only was sent to the committee that vets former administration officials' books and someone, presumably either serving on this committee or somewhere within the National Security Council decided to make a copy and send it to the newspaper. Absolutely extraordinary. Or perhaps not. Trump has known almost ever since he came to power that he does not attract total loyalty among his closest advisers. But this is a serious breach of confidence and loyalty. The timing of the leak is also so obvious. The Senate trial of Trump on impeachment charges has got to the point where a decision has to be made about allowing or banning witnesses from appearing before the Senate. The House members want it, a few Republican Senators are wavering and Senator Mitch McConnell, Senate Republican leader, is determined to forbid witnesses from appearing. So bang! The New York Times publishes the juiciest morsel from the Bolton book which makes it clear, in Bolton's memory, that Trump categorically stated he wanted the Pentagon to withhold the near-$400 million due to the Ukrainian government to fight off the pesky Russians in eastern Ukraine, UNTIL the Kiev government under the newly elected President Zelensky had agreed to investigate and dig up dirt on Joe Biden, Trump's main Democratic rival for the 2020 election. Well, you might argue, the Democrats have been claiming this for weeks/months. It's the notorious quid pro quo which lies at the heart of the impeachment charge and which Trump has always denied. But ths is Bolton saying it, or writing it. Few people are closer to the president than the national security adviser. If Bolton recalls those were the words of Trump, then most people would probably believe it to be true. So of course now the Democrats are even more insistent that Bolton must give evidence to the Senate trial. He didn't appear in the House stage of the impeachment process because he had been ordered not to appear by the president, and Bolton did as he was told. But now Bolton's dramatic recollection has appeared in print it's going to be more difficult for McConnell to say no to witnesses. Either way, the Democrats are going to bring up the book contents at every available opportunity. Who leaked the manuscript? Was it someone in the National Security Council? The draft manuscript was sent to the NSC's records management division on December 30, so it has been sitting around for nearly a month. Either The New York Times got a copy some time ago and just bided their time to make the greatest impact, or it was delivered into their hands very recently and they rushed into print. Bolton's lawyers have accused the NSC of "corrupting" the pre-publication review process, although it has to be said the publicity will do the book's sales prospects no harm at all! Trump, for probably the 100th time since he became president, will be furious and will be regretting he ever appointed Bolton to be his national security adviser.