If Trump fails in his effort...I don’t see Biden there more than twelve months, and Harris is called upon to be President (the worst of all scenarios...even to moderate democrats).
Considering that what separates a moderate democrat from a regular democrat is being a bit slower to openly embrace the most radical positions of the hard communist wing, another year should see them all firmly in Harris’s bed.
I see him there for a little more than 2 years. That gives his Communist Whore the maximum time of 10 years to change the system and become President for Life.