Sounds like it was a recorded interview from the day after the west Virginia rally, if Trump had said anything earth shattering I have to imagine fox would have already announced it and not hold it till the next day..
Trump and Mattis sat at a table and between them were two empty chairs with place marks for the two missing Dems who were not willing to attend or cooperate. Trump emphasized the the Dems were invited but, "as you can see", they continued to hold up the process and were unwilling to meet. Mattis just had a few cursory words and voila - the conference was concluded. MUCH more coverage than the MSM would normally "allow" the POTUS.
This morning's interview push seems like the same tactic. Prior to the broadcast, the reporter just grinned when asked if Trump was going to fire Sessions and said she was not allowed to say. Trump's strategy worked - two of ours took a bullet for the team and so did many in the rest of the nation as the reporter really did make it seem like the interview contained BIG NEWS. And really - it was Trump making an important point in front of as many people as he could - it just wasn't about Sessions. So his reasons for possibly releasing paperwork got extreme levels of first hand coverage in a venue of his choosing he could otherwise not get. I do think this HAD to happen before he could release docs.
It's unfortunate that POTUS has to get out the laser pointer to reach the public but the MSM's betrayal of our country has brought us to this point.