Details can be found on Slack #general thread: Slack
Issue
When we stood up open-release/juniper.3 release on standalone server I was not able to access the edX Demonstration Course outline or courseware using the honor@example or audit@example.com accounts but was able to use the staff@example.com account sucessfully.
Error indicates 404 Page Not Found.
Resolution
Make sure to set the PREVIEW_LMS_BASE different than the LMS_ROOT_URL as shown below and restart the LMS service. This needs to be anyhow to make sure that you can preview changes from the edX Studio.
/edx/etc/lms.yml
PREVIEW_LMS_BASE: preview.juniper3.ew-test.com
LMS_ROOT_URL: http://courses.juniper3.ew-test.com
Still considering adding this as a bug for the platform but mentioned this to edX to see what they prefer to do.