Acquia provide a 'VCS' location so that Drupal can export config YAML files there. But it doesn't have write permission?
Here's me trying to run the drush config-export command over SSH:
d8sandboxxx2@d8sandboxxx2:~$ drush @d8sandboxxx2.dev config-export
Choose a destination.
 : Cancel
 : sync
 : vcs
The file permissions could not be set on /mnt/www/html/d8sandboxxx27iynasv9p9/docroot/../config/default. [error]
Please advise? It would be a pity to not be able to use one of the most awaited features in Drupal 8.