If an application is not acted upon by the area manager or the area manager's designated agent within a reasonable time after the filing of the application, or is denied in whole or in part, or if an award of food stamp assistance is modified or cancelled under any provisions of this part, the applicant or recipient may appeal to the department in the manner and form prescribed by the department, and shall be afforded reasonable notice and opportunity for a fair hearing by the department. Written notice of a right to a fair hearing shall be given to each applicant and recipient at such time as any action concerning the amount of benefits awarded to the individual is taken or at the time a decision is made on an applicant's eligibility for such assistance.