Various sources, second hand. I'm not the "rumors guy" but I know a handful of people who are. And they're legitimately plugged into rumors. We've been doing this for a long time (over a decade) and I get scuttlebutt from our text chains, which are overwhelmingly accurate.
The addendum to this is that I'm talking about it on a forum, not writing about it on the front page. That means it's unconfirmed but probably, at least in partially, accurate.