Which of the following would NOT be a valid reason to cancel a trip authorization?

The reason a traveler decided to extend the trip would not be a valid reason to cancel a trip authorization, because extending a trip does not negate the need for the initial authorization. In fact, extending a trip may require an updated authorization to cover the new travel dates and potentially additional expenses. A trip authorization is meant to approve travel plans as they are initially outlined, but it can be adjusted to accommodate changes such as extensions.

In contrast, changes in a traveler's schedule often necessitate cancellations or modifications to the trip authorization, and if plans for the trip are merely tentative, it would be prudent to cancel the authorization since the trip may not actually take place. Additionally, if a trip has been canceled before any expenses have been incurred, that provides a clear basis to cancel the authorization without any repercussions.