I just finished with the previous version of course, do I need to start all over again? seems like all the lectures have been upgraded. plus so much of new content. Does that mean that the exam is now much more difficult than before? Is there a way to know what content is carried forward so that I can skip those to save time.
With courses/exams like this, you will always get upgrades or alterations to the course.
My approach always has been to go through the course normally, sometimes even a few times.
If new content pops up, just watch that section – you do not need to redo everything for this one updated topic, sometimes it is only a slight alteration or some additional information that may have been missed or released.
Once you are ready and have gone through test preps etc and are happy with your studying and note taking – sit the exam.
Once you go and look at the course dashboard it will normally have a flag for New or Updated topics anyway, use that as the way to judge.
This is the same way I have got all my certs including speciality and professional ones.