Keeping old Komento post visible but not allowing new posts.

We would like to have our students (users) view older Komento-posts, but not make new ones. The posts are made on articles that are part of class material, but after the class is finished, we would like the students be able to view previously made comments but not continue to make them.

If we turn off Komento (not "enabled" or remove the classes from the category list, the Komento comments made just disappear and cannot be viewed....until Komento is enabled again. Some of the comments are valuable but we don't want older students continuing to comment on later class intakes, but still able to view the comments.

I get the feeling this is not possible but if you have any ideas that would be appreciated.

Thanks!