49 CFR 375.605 - How must I notify an individual shipper of any service delays?
(a) When you are unable to perform either the pickup or delivery of a shipment on the dates or during the periods specified in the order for service and as soon as the delay becomes apparent to you, you must notify the individual shipper of the delay, at your expense, in one of the following six ways:
(1) By telephone.
(2) In person.
(3) Fax transmissions.
(5) Overnight courier.
(6) Certified mail, return receipt requested.
(b) You must advise the individual shipper of the dates or periods you expect to be able to pick up and/or deliver the shipment. You must consider the needs of the individual shipper in your advisement. You also must do the following four things:
(1) You must prepare a written record of the date, time, and manner of notification.
(2) You must prepare a written record of your amended date or period for pick-up or delivery.
(3) You must retain these records as a part of your file on the shipment. The retention period is one year from the date of notification.