This feature would give a course instructor the ability to "lock down" messaging for quiz-taking users at the time quizzes (or similar items) are being taken. When creating the quiz, the creator would have an additional configuration option to turn this on for that specific quiz. Additionally, an amount of time could be specified at which the "lock" is removed. Once the quiz is completed and submitted, or the aforementioned time period has passed, users would be allowed to message again. If the user attempts to send a message when messaging is "locked" for them, Moodle would simply deny the request and provide an appropriate message to the user.