Feedback and grades should be released to all students per assignment, four working weeks after the due date.
There are two actions required to ensure that grades are released as letter grades to all students. Please follow the step by step guidance below.
Check that the grade centre column is displaying letter grades, not scores. If it is displaying scores, set the correct grading schema with the following instructions.
Navigate to Course Management, Control panel, Grade centre, Full grade centre.
The Grade Centre is a table, with students displayed along the rows and assignments down the columns.
To edit a column, select the contextual menu next to the title of the assignment column header and choose Edit column information.
Locate the Primary Display option and select either UnderGrad or PostGrad letter depending on the academic level of the module.
Use the Submit button to commit all changes.
Prior to the release date, the grade centre column should have been hidden from students when you set up the assignment or graded activity. On the release date, the column will need to be shown to the students following the steps below.
Navigate to Course management, Control panel, Grade centre, Full grade centre.
The grade centre heading should be shown without any images or icons next to it.
If the column heading has an icon next to it with a cross through it, then the grades are not visible to students. 
To quickly make a column visible to students, use the contextual menu next to the heading and choose 'Hide from students on/off' to toggle the visibility.
Your students will now be able to view their feedback and grades.