(a) An agent's authority under a durable power of attorney terminates when:
(1) the principal revokes the authority;
(2) the agent dies, becomes incapacitated, is no longer qualified, or resigns;
(3) the agent's marriage to the principal is dissolved by court decree of divorce or annulment or is declared void by a court, unless the power of attorney otherwise provides; or
(4) the power of attorney terminates.
(b) Unless the durable power of attorney otherwise provides, an agent's authority may be exercised until the agent's authority terminates under Subsection (a), notwithstanding a lapse of time since the execution of the power of attorney.