The NASA Administrator is the agency's leader, and (along with the Deputy Administrator) is appointed by the President and confirmed by the Senate. It has been common for each President to choose a new Administrator; in the meantime, an Acting administrator fills the role until the Senate approves a replacement. Wikipedia has a nice explanation for the line of succession that chooses the Acting Administrator.
Former Administrator Jim Bridenstein retired on inauguration day; since then, Steve Jurcyk serves as the Acting Administrator. Today, former U.S. Senator (from Florida) and STS-61-C astronaut Bill Nelson was nominated to be the next NASA Administrator.
What has typically happened to the Acting Administrator once a new Administrator takes office? Do they return to their old job? Retire?