BREAKING: Michael Flynn had 19 interviews with the special counsel's office, per the office, which says criminal investigation is ongoing in heavily redacted filing. 
Correction: 19 interviews with the special counsel's office or other DOJ offices.
Here's the main memo from the special counsel's office: documentcloud.org/documents/5425… / Here's the redacted supplemental memo: documentcloud.org/documents/5425…
The main point of the main memo: Mueller recommends no jail time for Flynn due to his "substantial assistance."
In the second memo — properly an addendum, not "supplemental" (apologies) — important to note that this is referring to a criminal investigation that would appear to be ongoing and conducted by an entity other than Mueller's office.
Although it technically doesn't tell us in the unredacted part that it is not elsewhere, the earlier note that Flynn had interviews with non-SCO folks at DOJ, as well as the spacing of the redacted material in the heading (see below) pretty much makes it clear it is not SCO.
As to Mueller's investigation, there is a lot there in part B. ...
First, we get "Interactions Between the Transition Team and Russia." There's a bit redacted there.
Then, as any lawyer will tell you, where there's a "i," there has to be, at least, a "ii." So, Flynn provided information worthy of note beyond the transition interactions. Those could be campaign or White House interactions with Russia, or something else altogether.
By my eye, there's likely a two-paragraph "ii" and a one-paragraph "iii."
Finally, Mueller says that Flynn's "early cooperation was particularly valuable," which is like a bear hug from Mueller in terms of how Team Trump will see it. And, oh my, that redaction is tantalizing.
OK, thanks for the comments. I'm pretty much won over to the idea that that's a very short section "C" and not a "iii," due to the way this is worded. (I still think it ~could~ be "iii" if it's a ~different~ part of the SCO investigation beyond Russia and just totally redacted.)
