“Districts” mean the following:
(a) District 1 (Southern California) consists of the Counties of San Diego, Imperial, Orange, Riverside, San Bernardino, Los Angeles, Ventura, Santa Barbara, Kern, and San Luis Obispo.
(b) District 2 (Northern California) consists of all counties not included in District 1.
The boundaries of any district may be changed by a two-thirds vote of the commission, which is concurred in by the director, to ensure proper representation by handlers. The boundaries need not coincide with county lines.