Using CiviCRM 4.7.17 with Drupal 7.54
CiviGroup Roles sync adds and removes Drupal users from Drupal roles when changes to CiviGroup groups are done one Contact at a time from the groups tab for the Contact. So the sync is set up correctly.
But when I add or remove Contacts to/from CiviGroup groups in bulk from a list of Contacts, the changes are not synced to the Drupal roles.
These are NOT Smart groups by the way.
Am I missing something? How can I do bulk add/remove Contacts in Civi and have the Drupal roles synced accordingly?
Thanks for any suggestions.