knapplc excellent explanaion as I expected but I have two unanswered questions after the press conference:
Why Thursday? Why not Monday?
Will the interm AD have the power to hire and fire?
Why today & not Monday? Maybe the conference room they used for the presser was booked until today?

But seriously, that's a good question. They said they made their decision yesterday, but there's no way the thought to fire Eichorst just occurred to them randomly on a Wednesday. My guess, they were talking with Riley, talking with Eichorst, talking with Regents & boosters, hiring a search firm and making sure they had all their stuff lined up before taking this step. It took a few days, and here we are.
If that's the case (and they didn't truly just wake up on Wednesday & decide to fire him)
that's a great sign. It means they're being careful and deliberate and making sure of their steps before moving forward. It means some of the more knee-jerk decisions we've made in the past 20 years may not be repeated. They may still make a mistake in their hiring, but they're going to do proper due diligence before they hire somebody, and that's a good first step.
Will the interim have the power to hire & fire? Probably, but only in extreme situations and only after consulting with Bounds & Green, I'm sure. Pretty unlikely any coaches are removed until the new AD is in place.