Section 1738. Retirement of employees

Employees of the authority shall be
  eligible to join the board of education retirement system as established
  in section twenty-five hundred seventy-five of  the  education  law  and
  pursuant to the usual rules of that system, provided that a new employee
  who  upon appointment by or transfer to the authority is a member of the
  New York city employees retirement system may remain a member of the New
  York city employees retirement system if,  within  ninety  days  of  the
  effective  date  of the transfer to or appointment by the authority, the
  employee exercises an election to do  so.  Furthermore,  the  retirement
  rights  of employees of the city board employed on the effective date of
  this title shall not be impaired by reason  of  the  enactment  of  this
  title into law.