When having a virtual repo the aggregates remote repo and local repo.
Lets say that there is some pcakage that its latest version is 3.9 in the remote endpoint.
While you have in you local repo the same package with version 3.8.
In case you run:
You will see in the response two results for "latest package" that have the </d:IsLatestVersion> tag, set true for both
Steps to reproduce:
1. Create virtual nuget repo that aggregates remote repo and local repo
2. Install some nuget package ( not the latest version)
3. Move the package you resolved to the local repo
4. Run in the browser: http://localost:8081/api/nuget/nuget/FindPackagesById()?id=<package>&$top=2&$filter=IsLatestVersion
5. You will see two results that are set as the "latest version"