A trust terminates if by its terms the trust is to continue only until the expiration of a certain period or until the happening of a certain event and the period of time has elapsed or the event has occurred. If an event of termination occurs, the trustee may continue to exercise the powers of the trustee for the reasonable period of time required to wind up the affairs of the trust and to make distribution of its assets to the appropriate beneficiaries. The continued exercise of the trustee’s powers after an event of termination does not affect the vested rights of beneficiaries of the trust.