I don't mean to spam the Moodle forums, but I posted this issue in the Gradebook forum when really it may be more appropriate for this one.
My school uses Moodle 2.4, and we are having issues with grades repopulating in the Assignment activity for students who have previously been in the class. This is after a course reset that removes grades and submitted assignments, and the "Recover old grades if possible" option is unchecked when re-enrolling the students.
I work at a small community college where, unfortunately, students retake classes often and typically with the same instructor (as they don't have many other options). This has become a big nuisance to the instructors here who have to manually delete all the grades they had previously entered for these students.
I have created an issue in the Moodle Tracker here: https://tracker.moodle.org/browse/MDL-42501