The New York Times (30 Dec 2017) reported that Australian officials passed information about the Papadopoulos conversation to U.S. counterparts after leaked Democratic emails appeared online. The Mueller report, as summarized by the New York Post (19 Apr 2019), placed the Australian pass on July 26, 2016—days after WikiLeaks began publishing stolen Democratic National Committee emails—and said the FBI opened its investigation a few days later on that information. Durham later wrote that FBI Headquarters received information from Australia on July 28, 2016. Those dates are not the same sentence. Keep the layers.
How the information moved—Canberra cable, Joe Hockey in Washington, or Downer to the U.S. Embassy in London—has been described differently in later commentary (including Kimberley Strassel, as recapped in Australian coverage). This site does not pick one routing as FACT without the cable. What official U.S. reviews later treated as the opening information is the next post.
A diplomatic report is not an indictment. It is not a finding that Papadopoulos committed a crime at the wine bar. It is not a finding that Downer committed one by reporting.