Notwithstanding the provisions of any general or special law to the contrary, an employee as defined in Section 1 of the chapter 32 of the Massachusetts General Laws who is classified in either Group 1 or 2 and all political subdivisions thereof who has been a member for not less than thirty years in the aggregate shall be eligible to apply for and receive a service based retirement allowance as authorized by section five of Chapter thirty-two, using the 2.5 factor under subparagraph (a) of paragraph (2) of section five of chapter thirty-two, regardless of age, providing that the employee agrees to fully fund their pension benefit up front. The employee’s total amount due into the pension system is to be determined by  the State Retirement Board in order that the employee reach a 75% pension benefit (30 years) or 80% benefit (32+ years). The employee may use their vacation time allowance and/or personal allowance to pay that amount so determined by the Board.