S.C. Code Ann. § 12-60-440
The department may not assess a deficiency until thirty days after sending the proposed assessment as provided in Section 12-60-420, or, if the taxpayer files a timely written protest with the department, until the taxpayer's appeal is finally decided. For purposes of this section, the final decision of an appeal includes the decision of the Administrative Law Judge Division, DMV hearing officers, or court, if the matter was heard by the Administrative Law Judge Division or DMV hearing officers, or appealed to a court as provided in this article. This restriction on assessments does not apply to:
(5) assessments as provided in Section 12-60-910.
If a proposed assessment was not issued, the taxpayer may request an abatement of any assessment due to a mathematical or clerical error, or for a penalty described in item (3), within thirty days of the date of the assessment. Upon receipt of the request for abatement the department shall abate the assessment. Any further assessment of the tax with respect to which an abatement is made under this paragraph is subject to the proposed assessment procedures described in this chapter. No levy or collection proceeding may begin for a mathematical or clerical error during the thirty-day period during which a taxpayer may request an abatement.