For example: Biden gets sworn in. Then, prior to Biden dismissing the the Trump cabinet, the Trump cabinet uses the 25th amendment to relieve Biden, Harris, and other members of Congress of their duties for high crimes and misdemeanors (treason, election fraud, crimes against humanity, etc.).
For Trump's statement, see 1:56 of https://rumble.com/vcpol3-president-trump-full-speech-delivers-remarks-in-alamo-tx-jan-12-2020.html
My thought was that the simple act of trying to use the 25th amendment to remove POTUS is in itself insurrection.