8:26PM student is logged in looking at course FOO
9:15PM student logs in again to look at course FOO
9:15PM enrol\database\cli\sync.php runs and enrolls student in course FOO
There was no unenrollment from the course between the two times.
Grades posted prior to this happening are gone, grades posted after are available.
Activity logs for the the student show activity going back months.
Is there something that logging in at the same the enrol sync runs that could cause this?