Hi, I took and passed the 400 course earlier this year. In my opinion the difficulty in the 400 comes from the large amount of material you learn each day, which you then need to put in context and apply to the scenario at the end of that same day. The concepts themselves are not particularly difficult if you have scripting or programming experience. If you stay organized and take good notes you should be fine.

@lucrania thanks for the post. 

I am also scheduled to take the 400 course in about a month and am super nervous. 

Can you be more specific in regards to scripting? 
Are we asked to write scripts from scratch? Are those scripts taught previously that day? 
Can you point me to some material/sites I should focus on? 

thanks

I don't think I can get too specific without violating jamf's training policy. The topics in the course page are pretty accurate to what I learned in my class: https://www.jamf.com/training/online-training/remote-400/ ; in terms of bash there's loops, variables, control flow, interacting with the jamf API, etc.