53.9. In the case of employees who hold pensionable employment for which the basis of remuneration is 260 days, the pensionable salary paid by a body designated in Schedule III to this Act or Schedule II.1 to the Act respecting the Government and Public Employees Retirement Plan (chapter R-10) to an employee who is released with pay to hold pensionable employment under this plan with an association representing management personnel or for union activities during a year must be subtracted, for the purpose of computing the adjusted pensionable salary for the year, from the pensionable salary established under sections 25 to 28.1. The pensionable salary paid to the employee by the body or association is deemed to be, for the purpose of computing the annualized pensionable salary for the year, a lump sum attributed to the year under section 53.20. In the case of employees who hold pensionable employment for which the basis of remuneration is 200 days, the basic salary paid by a body designated in Schedule III to this Act or Schedule II.1 to the Act respecting the Government and Public Employees Retirement Plan to an employee who is released with pay to hold pensionable employment under this plan with an association representing management personnel or for union activities during the period referred to in the first paragraph of section 53.8 is deemed to be, for the purpose of computing the annualized pensionable salary, a lump sum attributed to the year under section 53.20.