A. Except as provided in §B of this regulation or by prior agreement of the parties, the administrative unit shall serve all notices, orders, and other documents in one of the following ways:
(1) By personal delivery;
(2) By mailing a copy of the document, first class, postage prepaid, to the person's last known business or home address; or
(3) If the person is represented by counsel, by delivering or mailing a copy of the document, first class, postage prepaid, to the person's attorney.
B. The administrative unit shall send the hearing notice to the person against whom the action is contemplated by certified mail to the person's last known address:
(1) At least 20 days before the hearing; or
(2) If the parties have agreed to a date for which 20 days notice cannot be given, at the earliest time possible.
C. If service of a hearing notice cannot be made under §B of this regulation, notice may be given under State Government Article, §10-209, Annotated Code of Maryland.
D. Service under this regulation is effective on receipt.
E. Unless the evidence shows otherwise, a document served by mail under this regulation is presumed to have been received by the addressee 3 days after the date the document was mailed.
F. Service of a subpoena shall be made under Regulation .12 of this chapter.