Good morning, @andriarad.
It's great to see you back in the Community!
As of right now, we haven't been provided with information as to why the course has changed. However, you can go to our training and certification FAQ that has a section where you can submit feedback to our Product Developers:
Frequently asked questions about ProAdvisor training and certification
We encourage you and others to get in touch with our ProAdvisor Support if you have any other additional questions. Have a wonderful day!