An appeal to the Board may be filed by: a person aggrieved by a decision of the administrative officer or unit; or an officer or unit of Baltimore City affected by a decision of the administrative officer or unit. A person shall file an appeal within a reasonable time provided by local law or the rules of the Board by filing with the administrative officer or unit from whose action the appeal is taken and with the Board a notice of appeal specifying the grounds of the appeal. On receiving the notice of appeal, the administrative officer or unit from whose action the appeal is taken shall transmit to the Board all papers constituting the record of the action appealed. Unless the administrative officer or unit from whose action an appeal is taken, after receiving the notice of appeal, certifies facts to the Board that the administrative officer or unit believes that a stay would cause imminent peril to life or property, an appeal stays all proceedings in the action appealed. If the administrative officer or unit provides facts showing that a stay would cause imminent peril to life or property, the proceedings may be stayed only by a restraining order granted by: the Board; or the Circuit Court for Baltimore City. A restraining order may be issued only: on application; for good cause shown; and after notice is given to the administrative officer or unit from whose action the appeal is taken. The Board shall: establish a reasonable time for the hearing of an appeal; give public notice of the existence of the appeal and of the hearing, and due notice to the parties in interest and to other persons entitled to notice under local law or the rules of the Board; and decide the appeal within a reasonable time. At a hearing, a party may: appear in person; or be represented by an agent or attorney. The Board may, in conformity with this title: wholly or partly reverse the order, requirement, or decision that is the subject of the appeal; wholly or partly affirm the order, requirement, or decision that is the subject of the appeal; or modify the order, requirement, or decision that is the subject of the appeal. The Board shall have the powers of the administrative officer or unit from whose action the appeal is taken.