On Drupal Stack Exchange, we had tags like 5, 6, and 7 for the Drupal version. All in a sudden, since today it is not possible to edit questions with those tags, even as moderators, because they aren't allowed anymore.
We have those tags since the site was in beta phase, when Stack Exchange decided not to allow tags like drupal-6 because users would have picked them just for the fact they contained Drupal and the question was about Drupal.
Are those number-only tags still allowed, or is Stack Exchange blocking them because a bug? Should we use a different tag schema for those tags, considering that
drupal-?\d+ tags are black-listed?