grades converting to overrides

Hi all,

We have a strange situation in Moodle 4.3 that we haven't seen before.  I thought it was user error, but now I'm questioning that.

The instructor created an assignment with grading method = scale which is defined as pass/fail.  To grade student submissions, he clicks on the assignment then clicks Grade.  In the right-hand pane, a drop down box appears with no grade/pass/fail as the three options.  He chooses "pass", then saves and proceeds to the next student.  

When he returns to the grading summary, the assignment shows that recent submissions still need grading.  We discovered that this happens when the assignment grades have the "override" checkbox checked (same as when the grades are entered directly in the grader report).  We unchecked the overrides, graded the items again (same way as before) and this time, they appeared correctly.  That is to say, there is no override in the grader report and the submission is recorded as graded on the grading summary.

I thought he was clicking the "not graded" link from the grade page, rather than choosing the grade from the dropdown menu.  When you click "not graded" you are redirected to the grader report, where you can select from the pass/fail dropdown and trigger the override.  But I confirmed that he is not doing this, so I am perplexed.

Thoughts appreciated!

Katie