Why are we unable to create new message base or configuration settings?

Environment:

Message Bases, Configuration Settings, Oracle B2C Service Updates

Issue:

The 'New' button to create a new message base and a configuration setting is grayed out on both our production and upgrade site.

Resolution:

The ability to create custom message bases and configuration settings is intentionally disabled on the upgrade site but allowed on the production site once the upgrade site is built. These new production records are retained at cutover with the default value.  NOTE: Referencing new custom message bases or configuration settings in PHP will cause File Sync to fail resulting in cutover delay.

Edits on the upgrade site to existing standard or custom message bases or configuration settings are retained at cutover. For example, if you disable SSO on the upgrade site to simplify your testing, you must undo your configuration setting edits before cutover. Otherwise SSO will be disabled in production after cutover.