S.C. Code § 6-17-160
If the governing body determines to exchange any refunding bonds, such refunding bonds may be exchanged privately for and in payment and discharge of any of the outstanding notes, bonds or other obligations of the municipality issued to finance or to aid in financing the acquisition, construction, improving, refinancing or improving and refinancing of an enterprise. The refunding bonds may be exchanged for a like or greater principal amount of such notes, bonds or other obligations of the municipality and the principal amount of the refunding bonds may exceed the principal amount of such outstanding notes, bonds or other obligations to the extent necessary or advisable, in the discretion of the governing body, to fund interest in arrears or about to become due. The holder or holders of such outstanding notes, bonds or other obligations need not pay accrued interest on the refunding bonds to be delivered in exchange therefor if and to the extent that interest is due or accrued and unpaid on such outstanding notes, bonds or other obligations to be surrendered.
S.C. Code § 6-17-160