The Secretary shall develop a pay plan for police employees, State Police communications operators, and State Police communications supervisors that includes the ranks and the grades within ranks that the Secretary considers appropriate. The pay plan under this subsection: is subject to approval by the Secretary of Budget and Management; and is effective on approval by the Governor only to the extent that sufficient money is included in the State budget. Each police employee, State Police communications operator, and State Police communications supervisor is entitled to receive the pay rate, including any increment based on length of service, set forth in the pay plan established under subsection (a) of this section. Each police employee is entitled to the pay rate for the next highest step within the police employee’s rank on: each July 1, if the police employee was a police employee on July 1, 1967; or each anniversary of the date of employment, for all other police employees. On promotion a police employee or a deputy State fire marshal is entitled to the pay specified for the new rank in the same step that the police employee or deputy State fire marshal occupied before promotion.