The writ of garnishment described in this article shall attach for so long as the defendant is employed by the garnishee and shall not terminate until the original arrearage is retired. The garnishee may rely upon the information as to the termination date of the duty of support of any individual claimed in the affidavit of garnishment, the amount of the duty of periodic support to be paid, any sums paid by the defendant between the date of the filing of the plaintiff's affidavit and the date of the initial answer of the garnishee, and the amount of the original arrearage existing as of the date of the affidavit of garnishment, unless the same are traversed by the defendant and the court enters any finding otherwise.