State Withholding Tax for Arkansas

While adding a new row on the “Update Employee Tax Data” for an employee in Arkansas we noticed on the “State Tax Data” page the M & S options are no longer available for the “Tax Status” field.  The only options available are 0, N and X.

The settings in the “SWT Marital Status Table” shows M & S as inactive with an effective date of 01/01/1999. But there are employees with M or S options after 01/01/1999.  Is it possible an update created this effective date and made those options inactive?