And then on Monday, the FBI warrant was executed.

The mystery is: What changed?

The answer, according to the Journal, is that an informant told the FBI that Trump was lying.

“[S]omeone familiar with the stored papers told investigators there may be still more classified documents at the private club after the National Archives retrieved 15 boxes earlier in the year, people familiar with the matter said,” according to the Journal. “And Justice Department officials had doubts that the Trump team was being truthful regarding what material remained at the property, one person said.”

And not only was Trump lying about retaining additional classified materials, according to the informant, this Trump insider knew precisely where they were.

That, at least, is the version of events described by Newsweek’s William M. Arkin, who was the first to report the existence of an informant, citing “officials” with “direct knowledge of the FBI’s deliberations.”