A provider shall enter into a written agreement with a participant on a form provided or approved by the Department that specifies the obligations of both parties, including: The services to be provided; The fees to be charged by the provider; If applicable, the amount of subsidy to be paid on behalf of the participant; and That the provider give at least 30 days notice of any proposed change in a fee charged by the provider for a particular service. The provider shall give one copy of the executed agreement to the participant and keep a second copy on file for 3 years after the termination date of the agreement. Any modifications to the agreement shall be reflected in an addendum signed and dated by both parties. A change in the amount of a participant's required contribution following a reassessment of the participant's financial eligibility: May be imposed immediately; and Is not subject to the 30 day notice requirement of §A(4) of this regulation.