You can choose either a 15-day or 30-day challenge.
The 15-day challenge demands a 2-3 hour daily time commitment, and the 30-day challenge requires about 1 hour per day.
However, regardless of which challenge you choose, you’ll get to maintain access for an additional 15 bonus days after the challenge ends. This way, if you get delayed at any point, you’ll still have a chance to acquire all the material.