For "Advanced" Web Programming, I don't really feel like you're hitting the mark by sticking with PHP. Sure, it works, and will probably get the job done for most web projects any of your students will ever work on, but if you want to get people excited while making them employable, it's important to teach new tools and frameworks. Unless the "Advanced" part is more about the techniques and patterns and less about the language, I think you're doing them a disservice by not branching out. And, of course, you can teach patterns and techniques in any modern language.

I'd expect to see some discussion of async job processing and front-end web frameworks in any advanced web programming course, high-school or college level. Honestly, just teaching the usual react stack with a typical node backend would probably be ideal since JS is approachable, react is still "cool", and you still only need to use one language.