Justin Baldoni says he now has cold hard proof Blake Lively and Ryan Reynolds had it out for him several months before she dropped her Christmas surprise lawsuit against him … so, now he’s updating his lawsuit against them.

According to new docs, obtained by TMZ, Justin alleges the “malicious and recklesss” defamation of his character started at least as early as October 31 — it’s got nothing to do with Halloween, and everything to do with the metadata embed in the New York Times article about Blake’s lawsuit against Justin.

Here’s their evidence … Justin’s team claims observers of the article found “viewing the HTML source code for the article revealed references to a ‘message-embed-generator’ that referred to a date of ‘2024-10-31.'”

So, in layman’s terms, and in Justin’s lawsuit … he says that shows the NYT started building the allegedly defamatory article no later than October 31 — the date the outlet developed a tool to display the text messages which were such a prominent part of Blake’s lawsuit and the Times article about it.

Team Baldoni says that’s significant because the elements behind the now infamous article “strip away the legal shields that Lively, the Times, and other Lively Parties were likely relying on to protect their malicious acts of defamation.”

As we’ve reported, Justin is suing the NYT for $400 million — separate from his suit against Blake and Ryan — alleging the outlet cherry-picked and doctored text messages in its article, and colluded with Blake to support her attack on his character.

Justin’s attorney Bryan Freedman tells TMZ … “The decision to amend our lawsuit was a logical next step due to the overwhelming amount of new proof that has come to light. This fresh evidence corroborates what we knew all along, that due to purely egotistical reasons Ms. Lively and her entire team colluded for months to destroy reputations through a complex web of lies, false accusations and the manipulation of illicitly received communications.”

Freedman adds, “The ongoing public interest in this case online has ironically shed light on the undeniable facts pertaining to The New York Times and how heavily Ms. Lively and her representatives were not only deeply involved in the attempted take down and smear campaign of Mr. Baldoni, Wayfarer Studios and their teams but that they themselves initiated it.”

The amended suit also includes a more than 150-page timeline that lays out, in meticulous detail, the sequence of Blake’s alleged campaign to destroy Justin. How detailed is it? It goes all the way back to January 1, 2019, when Justin emailed Colleen Hoover, the author of the “It Ends With Us” novel … and follows, step-by-step, through this saga to January 29, 2025.