You must notify the employee as soon as practicable after the employee's submission of the travel claim of any error that would prevent payment within 30 calendar days after submission and provide the reason(s) why the claim is not proper. However, not later than May 1, 2002, you must achieve a maximum time period of seven working days for notifying an employee that the travel claim is not proper.
41 C.F.R. §301-71.208