41 CFR § 302-17.65
What happens if I do not file the “Statement of Income and Tax Filing Status” in a timely manner?
June 9, 2020
The WTA is an advance on your income tax expenses, thus if you don't file the “Statement of Income and Tax Filing Status” in a timely manner, your agency will require you to repay the entire amount of the withholding and WTA (if any) that the agency has paid on your behalf.