(1) A member who first becomes a member on or after July 1, 2010 who no longer is working as a public school employee or in any other capacity for which service credit performed in this state is allowed under this act, on the member’s written application to the retirement system, is entitled to a retirement allowance provided for in section 84(1) if the member is 60 years of age or older and has accumulated 10 or more years of credited service pursuant to section 68 as a public school employee and has reached regular retirement age.

  (2) The eligibility requirements of subsection (1) must not be modified as provided in section 43b.

  (3) The reduction provided for in section 84(2) does not apply to an individual who retires under this section.

  (4) Notwithstanding any other provision of this act, a member who first becomes a member on or after July 1, 2010 shall not purchase or transfer service credit under article 4 and shall not have any purchased or transferred service credit included in the calculation of a retirement allowance on retirement.

  (5) Beginning October 1, 2019 and for each fiscal year in which an experience investigation study is completed under section 41(16), if the most recent experience investigation study of mortality of the retirement system using a 65-year-old based on a 50-50 male-female blend shows an increase of 1 or more years from the previous experience investigation study of mortality, the retirement board, in consultation with the actuary and the department, shall increase the regular retirement age by at least 1 year up to the total increase in whole-year increments unless the most recent actuarial funded ratio for the benefits funded under section 41b(3) is greater than 100% after accounting for an increase in mortality as reflected in the experience investigation study. Any adjustment to the regular retirement age by the retirement board must take place within 12 months after the retirement board’s adoption of the most recent experience investigation study on an effective date as determined by the retirement board. Any required increase to the regular retirement age under this subsection must take into account the cumulative increase in mortality relative to the experience investigation study covering the period 2012 through 2017, less any actual increase already taken into account in a previous increase to the regular retirement age. An adjustment to the regular retirement age under this subsection does not apply to a member who, on the effective date of the increase, is within 5 years of the then current regular retirement age. The retirement board may additionally exclude members who, on the effective date of the increase, are within between 5 and 8 years of the then current regular retirement age.

  (6) As used in this section, “regular retirement age” means the following:

  (a) For a member who first becomes a member on or after July 1, 2010 and before February 1, 2018, 60 years of age and is not subject to increase as provided under subsection (5).

  (b) Subject to subsection (5), for a member who first becomes a member on or after February 1, 2018, 60 years of age.