Hi David! The course itself is structured in a way to help people develop their skills in a way that makes sense, but after that, if you already have experience on some subjects, you are free to skip around the terms to find the lessons that will be the most beneficial to you at your current level. You can also freely go back to previous terms if you feel like you need it.
So it's alright to skip around the different terms. There's no real rules to it. Marc's not going to pop from your screen to tell you you're doing things in the wrong order, haha.