N.C. Gen. Stat. § 153A-59
If the structure of the board of commissioners is altered to establish a board with an odd number of members serving a combination of four-and two-year terms of office, the new structure shall be implemented as follows:
At the first election all members of the board shall be elected. A simple majority of those elected shall be elected for two-year terms, and the remaining members shall be elected for four-year terms. The candidate or candidates receiving the highest number of votes shall be elected for the four-year terms.
At each subsequent general election, a simple majority of the board shall be elected. That candidate who is elected with the least number of votes shall be elected for a two-year term, and the other member or members elected shall be elected for four-year terms.
N.C. Gen. Stat. § 153A-59
Union County, 2007 N.C. Sess. Laws 328, s. 1