A deputyship order generally remains in effect for as long as P lacks mental capacity, unless the order of court specifies that it is valid for a specific period of time or until the Court revokes it. If circumstances change, such as P regaining capacity or the deputy resigning, the order can be reviewed. Each case depends on its own specific circumstances.

Please refer to https://www.judiciary.gov.sg/family/deputyship for more information on deputyship applications in general.