Sec. 2. The following transitional provisions apply whenever a city changes into a first class city under this title:
(1) During the period before July 1 of the year in which the change occurs, the city shall be governed as if it remained a second class city.
(2) During the period after June 30 of the year in which the change occurs, the city shall be governed by an interim government under section 3 of this chapter.
(3) On January 1 following the year in which the change occurs, the city becomes a consolidated city.