PDA shall designate a reasonable number of representatives to assist in resolving grievances depending on geographical locations, hours of employment, and departmental organizational structure, notifying the Human Resources Director of the individuals designated. Alternates may be designated to perform such functions during the absence or unavailability of the designees. Representatives may be relieved from work duties by their supervisors to investigate and process grievances initiated by other employees within the same representation unit. Release time requests shall not be denied unreasonably. Representatives shall promptly report to PDA any grievances which may arise and cannot be adjusted on the job. Supervisory employees shall not represent non‑supervisory employees in grievances. Neither a representative nor PDA shall order any changes, and no change shall be made except with the consent of the department head.