Gowdy knew almost a year ago, Brennan lied under oath — "Do you know if the bureau ever relied on the Steele dossier as part of any court filings, applications?".. Brennan: "I have no awareness" — 5/23/17

the most important part of this exchange and anyone who really wants to see what Gowdy knew should watch the full version of their exchanges that day. Remember Gowdy is a respected prosecutor, he never asks a question he does not already know the answer too,thats how you get the people your asking the questions of to divulge the information you need .
The real part of this exchange that people especially now should be paying attention to is this in particular (for those with low attention span l will also link to the juiciest bit)just watch even Brennan’s body language.
Step outside the box-Watch the pattern of questioning it goes from putting him on the defensive to the final 2 kill shot questions in Gowdys allowed time.We go right from asking was Brennan aware of Ambassadors requesting unmasking, to who was requesting unmaskings right up to their last hour in office.What else has just been revealed to have happened in the last hours of Obama’s gang???Who else has claimed unmaskings were being asked for using their name without their knowledge???
Rep. Gowdy questions Brennan on Unmasking

Kill shot (watch the body language)

Longer version, l will direct link to Brennans after coming back from consulting with his advisor’s changing his answer on remembering on what really happened on one of the most important days of his life and he was in fact in the CIA offices on his last day in his final hours in office.Gone from being absolutely certain of what he was doing on a major day in his life,to maybe being advised records/videos/witness’s not part of the insurance policy/coup would be available of who was at the CIA offices on that day.This is the head of the CIA with years of training in keeping poker faced and committing to memory the smallest details, commenting on one of the most memorable days of his life

Full version of that days Gowdy/Brennan exchanges
h/t ClintonsWilDieInJail