I would not consider this bug as a critical one. First of all, if you change administrator user/password, then you need just to update openrc file on all the controllers. In case you want to do it automatically, using FUEL, you can use FUEL CLI and update access hash for admin user credentials, upload it and redeploy controller nodes by issuing HTTP PUT request to http://<fuel>:8000/api/deploy?nodes=1,3,5 . In case of cluster scale-up you can update cluster data the same way and simply click 'deploy changes' button that will redeploy all the controllers and update openrc file correspondingly.
I would not consider this bug as a critical one. First of all, if you change administrator user/password, then you need just to update openrc file on all the controllers. In case you want to do it automatically, using FUEL, you can use FUEL CLI and update access hash for admin user credentials, upload it and redeploy controller nodes by issuing HTTP PUT request to http://<fuel>: 8000/api/ deploy? nodes=1, 3,5 . In case of cluster scale-up you can update cluster data the same way and simply click 'deploy changes' button that will redeploy all the controllers and update openrc file correspondingly.