In the event an agreement expires before a new agreement has been approved by the employee organization, the employer representative and the legislature, the provisions of the expired agreement concerning (1) salary, excluding annual increments, (2) differentials, (3) overtime, (4) longevity, and (5) allowances for uniforms, which were implemented pursuant to approval by the legislature in accordance with section 5-278 shall remain in effect until such time as a new agreement is reached and approved in accordance with section 5-278. Nothing in this section shall affect the rights and duties of the employer and any exclusive employee representative designated to negotiate such new agreement under sections 5-271 to 5-280, inclusive, during the period of time after such agreement expires including the right to negotiate the extension of the expired agreement or any provision thereof not otherwise extended by this section. Notwithstanding any provision of a statute to the contrary, in the event an agreement expires before a new agreement has been approved by the employee organization, the employer representative and the legislature, the employer representative and the exclusive employee representative designated to negotiate such new agreement shall negotiate and agree upon payment of an exclusive payroll deduction of employee organization regular dues, fees and assessments and, upon reaching such agreement, such payment shall be made to such exclusive employee representative.