I have seen some great diaries around about having Biden pull a fast one on Republicans in the Senate by forestalling their swearing in, thus creating a Democratic majority and moving Garland’s nomination to confirmation. Why might you ask?
The Twentieth Amendment. Specifically Section 1:
Section 1. The terms of the President and Vice President shall end at noon on the 20th day of January, and the terms of Senators and Representatives at noon on the 3d day of January, of the years in which such terms would have ended if this article had not been ratified; and the terms of their successors shall then begin.
The old term ends at noon on the 3rd of January, and the new term for them/their successor begins at noon. The need to be officially sworn in is, well, not really necessary. The Constitution, via the 20th Amendment, makes it clear of when a new term begins for all members of federally elected office.
Hell, the oath for President is the only one specified in the Constitution, and thanks to the 20th Amendment it can be given at 12:32 PM on January 20th and it wouldn’t really matter as power was transferred automatically at 12:00 PM.
I hate to throw the cold water on this idea, but this is a Constitutional fact.