I think I found it...SAK-41512 

I was looking at this this morning just with Assignments (on nightly 19.0-rc01 on MySQL) and I agree with you Wilma on the other tools.  With regards to showing the Preview Rubric to the student, shouldn't the student also see the Graded Rubric not just the preview of it when they go into the Gradebook or the Assignment itself? I may be missing something but if the instructor is grading from the Rubric, I would want the student to see the graded rubric and how they attained their score. There's maybe another JIRA regarding this or I just missing something but your original comment was the first one I saw that that "somewhat" related.

The ability for students to preview the rubric previously existed in Assignments. I'm not sure why or when it was removed, but it was there at the time this JIRA was originally created, since the behavior in Assignments (where student rubric preview was available) is the desired behavior for all tools where rubrics are used.

SAK-40310: students are no longer able to preview rubrics in Assignments, and I think Assignments and Gradebook should be added to this feature request.

As of SAK-40310, the wording for the rubric has changed. The option is now to Hide the rubric, which means the student never sees it. If the rubric is not hidden, the student will only see if after it has been graded and the grade released to the student for Assignments, Gradebook and quizzes.