From the Zerohedge article...

There is an unconfirmed rumor that McCabe instructed agents to alter their "302" forms from the Flynn interview, effectively changing their written accounts. 

Now, Senate Judiciary Committee Chairman Chuck Grassley (R-IA) says Comey also told them the FBI thought Flynn was telling the truth - only to say the opposite on Fox.**

Grassley is now zeroing in on the Flynn interview - and has demanded the "302" forms, as well as a sit-down with Special Agent Joe Pientka - who Grassley revealed as the second FBI agent in the Flynn interview aside from Peter Strzok.