How to release Moodle Assignment Grades and feedback at specific time not using Marking Workflow

Go to Gradebook setup from the Administration block after you have finished setting up the Moodle Assignment.

Gradebook setup

Click on Edit next to the Assignment you wish to set and select Edit settings.

Edit settings

Tick Enable next to Hidden unitl and set the date and time that you wish to release.

Hide until

Click Save changes.