Section 606. Withdrawal of a member

(a) A member may withdraw as a member
  of a limited liability company only at the time or upon the happening of
  events specified in the operating agreement and in accordance  with  the
  operating  agreement.    Notwithstanding  anything to the contrary under
  applicable law, unless an  operating  agreement  provides  otherwise,  a
  member  may  not  withdraw from a limited liability company prior to the
  dissolution  and  winding  up  of   the   limited   liability   company.
  Notwithstanding  anything  to  the  contrary  under  applicable  law, an
  operating agreement may provide that a membership interest  may  not  be
  assigned  prior  to  the  dissolution  and  winding  up  of  the limited
  liability company.
    (b) A limited liability company whose original article of organization
  were filed with the secretary  of  state  and  effective  prior  to  the
  effective date of this subdivision shall continue to be governed by this
  section  as  in  effect  on  such date and shall not be governed by this
  section, unless otherwise provided in the operating agreement.