This refers to Moodle 3.2 from September 2017 onward.
The Post Date is when grades are released to students. It should be on or after the Due Date - usually after, giving enough time for marking to take place.
If anonymous marking is enabled, when the Post date and time for an assignment is reached, then the names of the students become un-anonymised, so the Post Date should be set to be after the end of the marking period.
When using Feedback studio, "Post Date" is when marked assignments will become visible to students. After the Post Date, students will be able to access both grade and feedback from you through the blue pencil icon.
It is not a good idea to change the Post Date - it should be set at the start. Changing it, especially after students have submitted, can result in student names and/or marks becoming visible in a way that cannot be changed back.
If you are having trouble with students not able to see their grades:
- Ensure that Module Gradebook settings allow students to view their grades, and that marks for the assignment are not hidden in the Gradebook.
- If the assignment is hidden altogether by setting Visible as Hide in the assignment settings then students will not be able to see their marks either, so it is best to use the Due Dates and Post Dates (or the Gradebook) to control visibility.
The following other resources are also relevant to this topic: