How long can an interim director serve?
Can be fired easy, right?
Get a real firebrand in there and clean up.
Might cause the Senate to approve an appointee if they think he would be ‘more reasonable’ than the firebrand.
Or leave firebrand in there as long as they are going to stall.
And if he screws up, or isn’t tough enough - You’re Fired! Then get another interim.
the Senate goes on leave over Memorial Day. Appoint an interim for 1 year then.
Interim serves until the replacement is nominated, cleared by the Senate, and appointed. Can be fired very easily, yes. As AndrewJackson pointed out, the president has a limited menu to choose from for this purpose, but he is not stuck with the normal chain of command replacement (McCabe in this case).
Acting Director and Interim Director can serve as long as Congress and the Prez allow. After Hoover died, the Acting Director served about a year.
Interviews are probably just to insult McCabe, or an indication that President Trump expects a long fight over a permanent Director.