S.C. Code § 12-6-3770
2016 Act No. 134, Section 1.B, provides as follows:
"B. This section takes effect in income tax years beginning after 2015. The provisions of this act are repealed on December 31, 2017, except that if the credit allowed by Section 12-6-3770, as added by this act, is earned before the repeal, the provisions of Section 12-6-3770 continue to apply until the credits have been fully claimed."