Final answer:
When a Change Transmittal contains information of a higher classification than the basic Directive, it means that the transmitted document contains more confidential or classified information.
Step-by-step explanation:
When a Change Transmittal contains or transmits information of a higher classification than the basic Directive, it means that the document being transmitted contains confidential or classified information that is of a higher level than what is originally specified in the Directive.
For example, if a Directive is classified as 'Confidential' and a Change Transmittal transmits information classified as 'Top Secret', the Change Transmittal is carrying information at a higher level of classification than the original Directive.
This is important because it highlights the need for strict control and protection of the Change Transmittal to avoid unauthorized access to the higher classified information.