To verify and edit the Due Dates:
  1. Go to onRecord > Settings > Grading
  2. Select Grade Plans
  3. Select the Grade Plan with the incorrect Attendance Totals and click View
  4. Verify the Due Date (This date should be the cutoff date for Attendance)
  5. If needed, click Edit to change the date
  6. Enter the correct date
  7. Click Save & Exit

Note: These changes only apply to the old Report Card Builder