a. Any contributor:
(1) who did not prior to filing an application to become an age-fifty-five-increased-benefits pension plan contributor as hereinafter in this subdivision a provided, file an application to become a twenty-year pension plan contributor pursuant to subparagraph (a) of paragraph one of subdivision a of section 13-547 of this chapter (relating to the twenty-year pension plan); and
(2) who is in member-service at the time of filing such application to become an age-fifty-five-increased-benefits pension plan contributor; may by a written application duly executed and filed with the retirement board on or after the date of enactment of this section and prior to July first, nineteen hundred seventy, elect to become an age-fifty-five-increased-benefits pension plan contributor commencing on July first, nineteen hundred seventy, and to contribute for the right to retire under the age-fifty-five-increased-benefits pension plan; provided, however that if any contributor filing such an application to become an age-fifty-five-increased-benefits pension plan contributor is not in member-service on July first, nineteen hundred seventy, such application shall be void and of no effect.
b. Any contributor in member-service on June thirtieth, nineteen hundred seventy:
(1) who is not, at the time of filing an application as hereinafter in this subdivision b provided, either a twenty-year pension plan contributor or a former twenty-year pension plan contributor who, by reason of cancellation, is an age-fifty-five-increased-benefits pension plan contributor pursuant to subparagraph (i) of paragraph two of subdivision d of section 13-547 of this chapter (relating to the twenty-year pension plan); and
(2) who is in member-service at the time of filing an application as hereinafter in this subdivision b provided: may by a written application duly executed and filed with the retirement board on or after July first, nineteen hundred seventy and no later than June thirtieth, nineteen hundred seventy-two, elect to become an age-fifty-five-increased-benefits pension plan contributor and to contribute for the right to retire under the age-fifty-five-increased-benefits pension plan.
c. The normal rate of contribution of each contributor making such an election pursuant to subdivision a or b of this section shall, commencing on July first, nineteen hundred seventy, be that which would have been established and in effect for such contributor on such July first if he or she had elected, as of his or her contribution rate fixation date, to become a twenty-five-year-age-fifty-five-one-per-centum contributor (as defined in subdivision forty-eight of section 13-501 of this chapter).
d. (1) Notwithstanding any other provision of this chapter to the contrary, but subject to the provisions of paragraph three of this subdivision, any contributor who, on or after July first, nineteen hundred seventy:
(a) enters member-service for the first time; or
(b) re-enters member-service as a withdrawn contributor without being entitled to service credit and status prior to withdrawal as provided for in section 13-506 of this chapter (relating to withdrawn contributors who re-enter service); or
(c) re-enters member-service after having become a discontinued member and is not entitled, at the time of such re-entry, to service credit and status prior to withdrawal as provided for in subdivision h of section 13-556 of this chapter (relating to credit for service and status prior to withdrawal upon restoration of a discontinued member to service); shall, upon such entry or re-entry into member-service, as the case may be, become an age-fifty-five-increased-benefits pension plan contributor and shall contribute as hereinafter provided in paragraph two of this subdivision d for the right to retire under the age-fifty-five-increased-benefits pension plan.
(2) The normal rate of contribution of each contributor who becomes an age-fifty-five-increased-benefits pension plan contributor pursuant to paragraph one of this subdivision d shall, commencing on the date of his or her entry or re-entry into member-service (as the case may be), be that which would have been established for such contributor if on such date he or she had been eligible to elect and had elected to become a twenty-five-year-age-fifty-five-one-per-centum contributor (as defined in subdivision forty-eight of section 13-501 of this chapter).
(3) The provisions of paragraphs one and two of this subdivision d shall be inapplicable to any contributor therein mentioned during any period wherein he or she is a twenty-year pension plan contributor by reason of (a) his or her election to become such a contributor pursuant to section 13-547 of this chapter (relating to the twenty-year pension plan) or (b) the provisions of paragraph five of subdivision b of such section 13-547 (relating to re-entry of twenty-year pension plan contributors into member-service).
e. (1) Notwithstanding any other provision of this chapter to the contrary, any contributor:
(a) who, on or after July first, nineteen hundred seventy:
(i) re-enters member-service after being a retired contributor immediately prior to such re-entry; or
(ii) re-enters member-service as a withdrawn contributor entitled to credit for service and status prior to withdrawal, by reason of qualification for such credit under section 13-506 of this chapter (relating to withdrawn contributors who re-enter service); or
(iii) re-enters member-service after having become a discontinued member and is entitled, at the time of such re-entry, to service credit and status prior to withdrawal as provided for in subdivision h of section 13-556 of this chapter (relating to credit for service and status prior to withdrawal upon restoration of a discontinued member to service); and
(b) who is not a twenty-year pension plan contributor by reason of his or her status at the time of such re-entry into member-service or by reason of an election made, after such re-entry, to become such a contributor pursuant to section 13-547 of this chapter (relating to the twenty-year pension plan); and
(c) who did not previously become a fifty-five-year-increased benefits pension plan contributor under subdivision a, b or d of this section; may, by a written application duly executed and filed with the retirement board within two years after such re-entry into member-service, elect to become an age-fifty-five-increased-benefits pension plan contributor and to contribute to the retirement system for the right to retire under the age-fifty-five-increased-benefits pension plan.
(2) the normal rate of contribution of any contributor making an election pursuant to paragraph one of this subdivision e, shall, commencing upon the date of his or her re-entry into member-service, be that which would have been established and in effect for such contributor on such date if he or she had been eligible to elect and had elected, as of his or her contribution rate fixation date, to become a twenty-five-year-age-fifty-five-one-per-centum contributor (as defined in subdivision forty-eight of section 13-501 of this chapter).
f. In any case where the provisions of law under which a contributor may elect to become a twenty-five-year-age-fifty-five-one-per-centum contributor were not in effect on the contribution rate fixation date of a fifty-five-year-increased-benefits pension plan contributor for whom a normal rate of contribution is required to be fixed pursuant to subdivision c or e of this section, such rate shall be determined in the same manner as if such provisions of law had been in effect on such date and thereafter.