An employing unit, not otherwise subject to this Chapter, which files with the administrator its written election to become an employer subject hereto for not less than two calendar years, shall, with the written approval of such election by the administrator, become an employer to the same extent as all other employers, as of the date stated in such approval, and shall cease to be subject hereto as of January 1 of any calendar year subsequent to such two calendar years, only if during the first calendar quarter ending March 31st of such year, it has filed with the administrator written notice to that effect, or the administrator on his own motion has given notice of termination of coverage.
La. R.S. § 23:1573