S.D. Codified Laws § 29A-3-612

Except as otherwise ordered in formal proceedings, the probate of a will subsequent to the appointment of a personal representative in intestacy, the probate of a later - offered will which supersedes the formal probate of another will, or the vacation of an informal probate of a will under which the personal representative was appointed, does not terminate the appointment of the personal representative although the personal representative's powers may be reduced as provided in § 29A-3-401 . Termination occurs upon appointment in informal or formal appointment proceedings of a person entitled to succeed to the appointment under the new testacy status. If no request for new appointment is made within thirty days after expiration of time for appeal from the order in formal testacy proceedings, or from the informal probate, changing the decedent's testacy status, the previously appointed personal representative may continue as personal representative under the subsequently probated will, or in intestacy, as the case may be.

Source: SL 1994, ch 232, § 3-612.