Nothing in this chapter shall be construed in any way to affect, alter or modify the existence of municipalities now operating under Chapter 108 of the Laws of 1908. Such municipalities shall continue to enjoy the form of government now enjoyed by them, and each shall be possessed of all rights, powers, privileges and immunities granted and conferred by Chapter 108 of the Laws of 1908. The mayor and commissioners of all municipalities now operating under Chapter 108 of the Laws of 1908 shall hold their offices for a term of four (4) years, and until their successors are duly elected and qualified. The officers shall qualify and enter upon the discharge of their duties on the first day of July after such general election that is not on a weekend, and shall hold their office for four (4) years, and until their successors are duly elected and qualified.