Ambiguity with Capabilities.ChangeTracking annotation

Suppose I have an entity type with 2 structural properties (A, B) and 2 navigation properties (C, D).

Then I use :

<Annotation Term=”Capabilities.ChangeTracking”>

  <Record>

    <PropertyValue Property=”FilterableProperties”/>

      <Collection>

        <PropertyPath>A</PropertyPath>

      </Collection>

    </Record>

</Annotation>

Now it is clear that A is filterable and B is not. But how is the client to interpret ExpandableProperties not being specified (defaults to an empty Collection(NavigationPropertyPath))?

1. The server omitted these properties from the annotation because they (C, D) are all expandable.
2. The server omitted these properties from the annotation because they (C, D) are not expandable.

The interpretation of an empty collection here is ambiguous.