Question: has a president ever changed vice presidents?
Answer: Two vice presidents have briefly acted as president under the 25th Amendment: George H. W. Bush on July 13, 1985, and Dick Cheney on June 29, 2002 and on July 21, 2007. ... Two vice presidents—George Clinton and John C. Calhoun—served under more than one president. There are currently five living former vice presidents.