It is tradition to allow them to fly home in the planes. They don't get to use to call sign unless they are still in office. Obama flew in freaking Marine One right after Trump took office. Trump flew back PRIOR to the office switch and Pence flew home after because he attended the event. Both planes are now switching back to their intended use.

After they sweep them for bugs and bombs cause let's face it they can't afford to be recorded committing treason.

Bottom line the planes aren't still being used by the 45 admin. Quit making shit up.