Section 298.23 - Notifications to the Department of change in operations(a) If any of the information contained on its registration changes, an air taxi operator shall submit an amendment reflecting the updated information. This amendment shall be filed no later than 30 days after the change occurs. There is no filing fee for submitting an amendment.(b) An amendment shall be made by resubmitting OST Form 4507 to the Department of Transportation, Federal Aviation Administration, Technical Programs Branch (AFS-260), 800 Independence Avenue SW, Room 831, Washington, DC 20591. If the air taxi operator has a mailing address in the State of Alaska, the form shall be mailed to the Department of Transportation, Federal Aviation Administration, Alaskan Region Headquarters Technical Standards Branch, (AAL-231), 222 West 7th Avenue, Box 14, Anchorage, Alaska 99513. 70 FR 25768 , May 16, 2005, as amended by DOT-OST-2014-0140, 84 FR 15935 , Apr. 16, 2019