Projects feature - cannot update changes made to the core document version

For the Projects feature, the Update button does not show up when changes are made to the core version of a document. This would mean that once a document is added to a project, any changes made to the core version of the document will be lost when the project is merged. The documentation  https://xmdocumentation.bloomreach.com/library/end-user-manual/projects/make-changes-to-core.html gives the impression that even documents can be updated. The 'Update' option also does not show up when you add a new Experience page and add new components to the xpage.

Steps to Reproduce

Scenario 1

• Create a project without specifying campaign start and end dates
• Add a channel to the project and a document from the same channel
• Add and Publish new changes to "core" version of the document
• Add new changes to "projects" version of the document
• Update button does not show up in the Projects view
• If you merge the project at this point, changes made to the core version are overridden

Scenario 2

• Create an experience page and add a new component to the page
• Update button does not show up in the Projects perspective

Is this intended behavior? This is preventing them from making any changes to the core version of the document while working on a project.