Find the assignment title on the sidebar and click on it to open the assignment overview. Click "Edit Dates" to open up the editor.
After selecting "Edit Dates" a new window will appear:
Then click on the calendar in the upper right corner of the date and time box, this will allow you to change the date and time.
*Submission and peer grading can't overlap. But you can set hand-in time to close as the same time peer grading opens.
Need to allow students to hand-in or give feedback past the deadline? Learn how here.