Since last November, when Mick Mulvaney became acting director of the agency formerly known as the Consumer Financial Protection Bureau, he’s steered it away from many of the practices his predecessor had embraced. Questions have arisen about how long Mulvaney can serve in that capacity, which is supposed to be temporary. The answer: until 2025, at the latest.

President Trump appointed Mulvaney to the position of acting director under the Federal Vacancy Reform Act of 1998 (FVRA). That law limits a president’s ability to install people in high executive roles through supposedly temporary assignments. The FVRA prevents a scheming president from getting around term limits for various federal officials, which can be done by having an individual first work in a temporary capacity and then later formally appoint him, with the advice and consent of the Senate. That sort of artifice could, for example, extend the five-year term of the director of the Bureau of Consumer Financial Protection (its statutory name and the one Mulvaney now insists on using) to nine years, if that person were appointed acting director early in a presidency and then confirmed by the Senate four years later, in the last year of the president’s term.

The FHVA limits the time a person can serve as an acting official to 210 days after the vacancy arose. That time can be extended if the president formally nominates someone for the position, and that extension continues through the time the nomination is pending. If that nomination is unsuccessful, the president can again extend the acting official’s tenure by nominating another person and awaiting that individual’s confirmation. A nomination can fail if the Senate rejects it, the nomination is withdrawn, or the nomination is returned with no action—which occurs for instance if the Senate term ends before the nomination is acted on.

Doing the math for an extended Mulvaney tenure shows that he could head the BCFP until 2025. That would require: President Trump to nominate a CFPB director this June; that nomination to be returned with no action in December 2018, when the current congressional term ends; Trump to nominate Mulvaney to that same position in July 2019; and that nomination to be approved in December 2020. That sequence of events would leave Mulvaney in office until 2025.