You are able to enrol into a course up to Day 5 of the course.
Keep in mind that the first module deadline will be on Day 10, so you will have 5 days to catch up on Module 1 and complete the first assignment.
If you choose to enroll in a course after Day 5, you will automatically be placed into the next term course start date. This means that your course will start on the 1st of the following month.