“His time is short. He’ll be out and gone sometime after this coming Friday, the 20th.”
What is the significance of the 20th?
If Biden dies or is otherwise removed from office after Jan. 20 - i.e., after having held the office for a full two years - then his successor could theoretically complete the remainder of his term, and then still go on to be elected president twice.
If, however, Harris were to succeed him prior to Jan. 20, then she could finish his term - but could be elected only once.
Regards,
Brandon’s POTUS term will be more than halfway complete, so whoever replaces him will be able to tack a free two extra years on top of his or her two full terms in office.