(D) Contributions to each investment trust account created under this chapter by a resident of this State or a nonresident required to file a State of South Carolina income tax return are deductible from South Carolina income subject to tax up to the limit of maximum contributions allowed to such accounts under Section 529 of the Internal Revenue Code of 1986, as amended, including funds transferred to an investment trust account from another qualified plan, as allowable under Section 529 of the Internal Revenue Code of 1986, as amended, and to the extent that the transferred funds were not permitted a state income tax deduction previously under South Carolina law. For purposes of this subsection, the term "qualified plan" means any plan qualified under Section 529 of the Internal Revenue Code of 1986, as amended.
State income tax deductions as provided for in this section may be taken in any taxable year for contributions and rollovers made during that taxable year, and up to April fifteenth of the succeeding year, or the due date of a taxpayer's state income tax return excluding extensions, whichever is longer.