The “understanding” was based on phone calls that were under surveillance through the FISA warrants.
Which are the poison fruit that can never be used once ELLIS FINISHES WITH THEM. Also.the FBI interpretation is and was highly biased.
Flynn initially denied to others in the administration that the conversations involved U.S. sanctions against Russia. But intercepts of Kislyaks phone calls showed otherwise. Washington Post columnist David Ignatius reported that Flynn and Kislyak indeed discussed sanctions. Ignatiuss leaker was a U.S. government official who has yet to be identified.