There is also a story out today that the FBI may have first leaked stories to the press and then used those stories to obtain FISA warrants.
http://www.foxnews.com/politics/2018...-warrants.html
If they did this in relation to the Carter Page warrants then it's likely that any evidence obtained from those warrants will be inadmissible in court. That would, for all practical purposes, make the entire Mueller probe a moot point.