There shall also be filed with the court administrator proof of mailing of such account to the last addresses known to the trustee of, or of the service of such account upon, such of the following beneficiaries or their natural or legal guardians as are known to, or reasonably ascertainable by, the trustee:
Service shall be sent by electronic means in accordance with Rule 14 to any party that has agreed to or is required to accept electronic service under Rule 14.
Minn. Gen. R. Prac. 417.04