Prediction: Harris is installed under the 25th amendment. Buys herself some goodwill as a take-charge gal by immediately firing Austin, Milley, and Mayorkas, which buys her 6-months. She installs new minions with same mission, while the Democrats rally around her to try and save their 2022 chances, which (rightly) look pretty bleak right now.
I look for Harris to insist on a state funeral for Biden and a long period of national mourning in which it will be impolite to mention politics or human-caused disasters.
Her debacle in her on stage debut with the border made her damaged goods...they probably want to continue propping up Biden after seeing that.