; and (ii) in connection with such findings, may exempt from the 6-month time period described in paragraph (1)(A), for a reasonable period of time a class of providers of voice service, or type of voice calls, as necessary for that class of providers or type of calls to participate in the implementation in order to address the identified burdens and barriers. (B) Full participation The Commission shall take all steps necessary to address any issues in the findings and enable as promptly as possible full participation of all classes of providers of voice service and types of voice calls to receive the highest level of attestation. (C) Alternative methodologies The Commission shall identify or develop, in consultation with small providers of service and those in rural areas, alternative effective methodologies to protect customers from unauthenticated calls during any exemption given under subparagraph (A)(ii). Such methodologies shall be provided with no additional line item charge to customers. (D) Revision of exemption Not less frequently than annually after the first exemption is issued under this paragraph, the Commission shall consider revising or extending any exemption made, may revise such exemption, and shall issue a public notice with regard to whether such exemption remains necessary. (4) Accurate identification The regulations required by subsection (a) shall include guidelines that providers of voice service may use as part of the implementation of effective call authentication technology under paragraph (1) to take steps to ensure the calling party is accurately identified. (5) No additional cost to consumers or small business customers The regulations required by subsection (a) shall prohibit providers of voice service from making any additional line item charges to consumer or small business customer subscribers for the effective call authentication technology required under paragraph (1). (6) Evaluation Not later than 2 years after the date of enactment of this Act, and consistent with the