My guess is that Joe's angry that he was forced out.
He's losing his marbles. But at the moment, he knows he's still the President of the United States.
But at this rate, he won't be able to remember his name in November. It appears to me that he's getting worse each say. So they're not able to hide his condition from the American public anymore (obviously).
They used the, “:I’ll announce today, give a public address sometime later this week, TBD” excuse.
Why not give the address today or wait a day or two and give it then to get everything in order. All very important questions.