I've searched the the thread for help on changing the IP address on the machine and can't find what I need. I am following the standard Ubuntu instructions for changing to a static IP address, but after hitting "Apply" and toggling the switch the network settings don't change. Is there something particular about the Apollo setup that is preventing me from changing the IP address?
There shouldn't be anything Apollo-specific, no. For what it's worth, the device is running Armbian, so looking for Armbian-specific instructions may give you better results.
https://www.albertogonzalez.net/how-to-set-a-static-ip-on-armbian/You may want to look into using your router dashboard to assign static IPs, if it doesn't work through your OS.