(1) Subject to subsection (2) of this section, the authority and responsibility of a guardian for an incapacitated person terminates upon the death of the guardian or ward, the determination of incapacity of the guardian, or upon removal or resignation as provided in section 15-5-307[, Idaho Code,] of this part. Testamentary appointment under an informally probated will terminates if the will is later denied probate in a formal proceeding. Termination does not affect his liability for prior acts nor his obligation to account for funds and assets of his ward.
(2) If the conditions set forth in section 54-1142(1)(j)[, Idaho Code,] exist, then the guardianship shall continue as set forth in that section.