Back in my first post on the structure of Robert Mueller’s team, “Robert Mueller’s Grand Jury and the Significance of Felix Sater,” I noted that he would know what he was dealing with because of past history with Felix Sater, the sometimes business partner of Donald Trump, who has served as an FBI informant on (among other things) the mob.

In BuzzFeed’s fascinating story on Sater’s past as an intelligence and FBI informant, Anthony Cormier and Jason Leopold go further. They point out that Andrew Weissmann signed Sater’s FBI cooperation agreement and Sater has ties with another five members of Mueller’s team.

Today, as he is being questioned about Trump’s business deals and ties to Russia, he has built relationships with at least six members of special counsel Robert Mueller’s team, some going back more than 10 years. [snip] Signing Sater’s cooperation agreement for the Department of Justice was Andrew Weissmann, then an assistant US attorney and now a key member of the special counsel’s team. Mueller himself would be the FBI director for most of the time Sater served as a source.

The mob and fraud and corruption lawyers working for Mueller have a remarkable amount of firsthand knowledge about who Felix Sater is.

Which is why I find the timing of the interviews Sater has had with the three main Russia investigations to be so interesting. These are:

December 2017 [Leopold clarified this via Twitter]: Mueller interview December 2017 [CNN has reported it occurring on the 20th]: HPSCI interview in lawyer’s office April 2018: Scheduled interview with SSCI

This, in spite of the fact that Sater’s role in helping pitch a Ukrainian peace deal to Mike Flynn first got reported in February.

A week before Michael T. Flynn resigned as national security adviser, a sealed proposal was hand-delivered to his office, outlining a way for President Trump to lift sanctions against Russia. [snip] The amateur diplomats say their goal is simply to help settle a grueling, three-year conflict that has cost 10,000 lives. “Who doesn’t want to help bring about peace?” Mr. Cohen asked. But the proposal contains more than just a peace plan. Andrii V. Artemenko, the Ukrainian lawmaker, who sees himself as a Trump-style leader of a future Ukraine, claims to have evidence — “names of companies, wire transfers” — showing corruption by the Ukrainian president, Petro O. Poroshenko, that could help oust him. And Mr. Artemenko said he had received encouragement for his plans from top aides to Mr. Putin. [snip] Mr. Artemenko said a mutual friend had put him in touch with Mr. Sater. Helping to advance the proposal, Mr. Sater said, made sense. “I want to stop a war, number one,” he said. “Number two, I absolutely believe that the U.S. and Russia need to be allies, not enemies. If I could achieve both in one stroke, it would be a home run.” After speaking with Mr. Sater and Mr. Artemenko in person, Mr. Cohen said he would deliver the plan to the White House. Mr. Cohen said he did not know who in the Russian government had offered encouragement on it, as Mr. Artemenko claims, but he understood there was a promise of proof of corruption by the Ukrainian president. “Fraud is never good, right?” Mr. Cohen said. He said Mr. Sater had given him the written proposal in a sealed envelope. When Mr. Cohen met with Mr. Trump in the Oval Office in early February, he said, he left the proposal in Mr. Flynn’s office.

And in spite of the fact that Sater’s role in pitching a Trump Tower deal became known at least as early as August, when Michael Cohen reported it to Congress.

While Donald Trump was running for president in late 2015 and early 2016, his company was pursuing a plan to develop a massive Trump Tower in Moscow, according to several people familiar with the proposal and new records reviewed by Trump Organization lawyers. As part of the discussions, a Russian-born real estate developer urged Trump to come to Moscow to tout the proposal and suggested that he could get President Vladimir Putin to say “great things” about Trump, according to several people who have been briefed on his correspondence. The developer, Felix Sater, predicted in a November 2015 email that he and Trump Organization leaders would soon be celebrating — both one of the biggest residential projects in real estate history and Donald Trump’s election as president, according to two of the people with knowledge of the exchange. Sater wrote to Trump Organization Executive Vice President Michael Cohen “something to the effect of, ‘Can you believe two guys from Brooklyn are going to elect a president?’ ” said one person briefed on the email exchange. Sater emigrated from what was then the Soviet Union when he was 6 and grew up in Brooklyn.

So even Mueller’s prosecutors, who know Sater well, waited at least four months before they interviewed him.

Plus, the timing of these interviews is interesting given the other known interview schedules (see this CNN timeline for the easiest comparison). Sater’s HPSCI interview, for example, took place the same week as long-time, loyal Trump assistant Rhona Graff got interviewed, at a time when Republicans had started blowing through interviews in an attempt to finish their investigation (HPSCI announced they were done with interviews today).

SSCI, by comparison, first tried to interview Michael Cohen — an important participant in both Sater roles — in September, but brought him back on October 25 after he released a public statement.

In Mueller’s investigation, Sater got interviewed around the same time the team was interviewing Hope Hicks and Don McGahn, really high level people with a good degree of personal exposure.

And of course, all of these interviews took place in the wake of the November 30 Mike Flynn plea deal, who reportedly received the Ukrainian pitch.

So December Mueller and HPSCI interviews and an April SSCI interview suggests that all parties, for different reasons, felt like they had to do a lot of work before bringing in Sater, in spite of the fact that he was an identified interest as soon as the Flynn concerns were raised. Remember, too, that the subpoena Mueller just issued to Sam Nunberg started at almost exactly the same time Sater was pitching that Trump Tower deal.

Mind you, I don’t know what to make of the timing. But I do find it interesting that Sater’s old friends didn’t immediately seek him out for his honest testimony.