Biden or whoever that was may have been "inaugurated" as "PRESIDENT OF US CORP", but not as Article II "President of the Republic". Also Biden was NOT "C-I-C of the CORP military", that role also appears to have been split off prior to 20JAN2021 in addition to "C-I-C of the Republic military" which Trump likely retained as required per his oath.
Biden or whoever that was may have been "inaugurated" as "PRESIDENT OF US CORP", but not as Article II "President of the Republic". Also Biden was NOT "C-I-C of the CORP military", that role also appears to have been split off prior to 20JAN2021 in addition to "C-I-C of the Republic military" which Trump likely retained as required per his oath.