(4) Guidelines for spectrum refarming for improving spectrum utilization. The Master Plan for Spectrum Management shall come into force upon its publication in the Government Gazette and shall be used as the criteria and preliminary conditions for licensing and any undertaking pertaining to the spectrum utilization. The NBTC shall monitor and evaluate the implementation of the Master Plan for Spectrum Management and revise the said Master Plan for the benefit of efficient spectrum management and be in line with the advancement of changing technologies. In preparing the Master Plan for Spectrum Management, the NBTC shall conduct a hearing to gather opinions from the public, the business operators using the spectrum and state agencies concerned in order to take those opinions into consideration. The time taken for a hearing shall not be less than thirty days. The preparing of the Master Plan for Spectrum Management shall give due regard to the national security as necessary. Section 49. In the Telecommunication business regulation, the NBTC shall prepare the Broadcasting Master Plan and the Telecommunications Master Plan so as to be a five-year implementation guideline. The plans shall be in accordance with the Master Plan for Spectrum Management and shall at a minimum provide guidelines for development and promotion of free and fair competition among operators, guidelines for spectrum licensing and business licensing. On the part of broadcasting services, the people sector shall be permitted to use frequencies for public interest and nonprofit for community service in a proportion of not less than twenty percent of frequencies allocated in each licensing area. In the preparation of the Master Plans under paragraph one, the NBTC shall hold a hearing from the public, the operators and state agencies concerned in order to take those opinions into its consideration. The time taken for a hearing shall not be less than thirty days. In the case where the NBTC’s decisions are conflicting with the opinions of the public, the operators or state agencies expressed at the hearing under paragraph two, the NBTC shall give further explanation and reasons to the said public, the operators or state agencies. The public, operators and state agencies under paragraph three who consider that the Master Plans as prescribed by the NBTC is conflicting with the provisions of the Constitution of the Kingdom of Thailand. There shall have the rights to lodge the case with the Administrative Court. There shall be deemed that the said Master Plan be the rules under the Act on Establishment of Administrative Courts and Administrative Court Procedure. The Master Plans under paragraph one shall oblige the NBTC and state agencies concerned upon the publication in the Government Gazette. Section 50. For the benefit of providing universal basic telecommunications and social services in accordance with the Telecommunications Business Act, the NBTC shall set forth a plan for universal basic telecommunications and social services in which it