The purpose of the on-demand course is to give you access to the study material, when you have the time to study. The entire course will therefore be ready when you log in and you will have full access to the course material for 8 weeks. During this time, it is entirely up to you when you study and how much time you wish to spend on each module.
There are certain tasks and assignments, which need to be completed in order to receive the Certificate of Participation at the end of the course, but you can go over the material as many times as you wish.
More information and registration