The Marking Period is set to end on 12:01 am on the end date that is set within the Marking Period.

For example, the Q3 Marking Period is set to end on 2/6 and Q4 Starts on 2/7.

What this means is as of 12:01 am on 2/6 the Q3 will stop displaying since Q4 has a Begin Date of 2/7, from 12:01 am 2/6 to 12:01 am 2/7 there is a 24 hour gap which changes the Gradebooks Display back to Q1 or the Prior Term because there is a gap in the Marking Periods. Rather than it display nothing it displays the prior or first term.

To fix this, You can change the Q3 marking period to end on 2/7 so teachers will have access to their assignments for the rest of the day and change the Q4 to start on 2/8. 

Then you can go in on the next day 2/7 and change the 2/8 date to 2/7 for Q4 and change Q3 back to 2/6 this way there is no gap between Q3 and Q4.
Teachers will not see Assignments due for 2/7 until you change the dates back on 2/7 for Q4 to 2/7 or you set the Display in their Gradebooks to show for a day later/earlier on the Term they would like that Assignment to show on.

To set the marking period dates:
  1. Go to onCampus > Settings > Academics > Marking Periods.
  2. Select the correct School Year.
  3. Select the correct School Level.
  4. Make note of the end date for the term.
  5. Edit the marking period under the term.
  6. Change the marking period's End Date to the last day of the term.
  7. Save & Exit.