Perusall sends email reminders to students 3 days, 2 days, and 1 day before the deadline of an assignment. Only students that have not started an assignment (or still have a grade of 0) will be sent a reminder.
Instructor course settings:
Reminders are enabled by default, but you can disable reminders for your course by unchecking Enable assignment reminders under Settings > Advanced > Library & assignments.
Student profile settings:
Students can also individually opt out of receiving such reminders by navigating to their user icon on the top right corner of their screen and select Manage notifications. Then uncheck Notify me when an assignment that I haven't yet completed is about to be due.
Related to