Did you already have SOFA, and it was pulled or denied? Here is THE definition from the regs..

Termination and Withdrawal of SOFA Status.

IC or TR designation shall be withdrawn by USFK under the following circumstances:

a. For Invited Contractors/Technical Representatives business entities, upon contract expiration date (as noted on the USFK Form 700-19A-R-E). For IC/TR employees, thirty days after contract expiration date; or

b. Determination the contractor or a contractor’s employee/employee’s dependents engaged in business activities in the ROK other than those designated by the U.S. Representative to the SOFA Joint Committee; or

c. Determination the contractor or a contractor’s employee/employee’s dependents engaged in practices illegal in the ROK, or in violation of the SOFA, or in violation of USFK regulations and policies.

d. USFK/FKAQ is responsible for processing all IC/TR terminations. USFK/FKAQ maintains the unilateral right to terminate IC/TR status upon sufficient evidence that contractor employees/dependents have engaged in practices illegal in the ROK, in violation of the SOFA and/or in violation of USFK regulations or policies. 

How many people fit into any of the above categories? Not many.

Once you have it, you should keep it.