(a) This section applies to each municipality unless the municipality's governing board files with the board of trustees before December 31, 2001, an election to not provide for five-year vesting. A governing board that elects to not provide five-year vesting may revoke that election by sending notice to the board of trustees to provide for five-year vesting.
(b) After December 31, 2001, a member may terminate covered employment and remain eligible to retire and receive a service retirement annuity at any time after the member attains an applicable age as provided by law if the member has at least five years of credited service performed for one or more municipalities to which the five-year vesting provision under this section applies.