thanks for your reply Jim. Although I use the nightly builds almost exclusively, I always have a stable version on an SD card to fall back on. I also have the Stellarmate OS which is dependable. So, all devices are working fine (including my ASI EAF) in the stable version.
I'm guessing it was about two weeks ago after a nightly update that my ASI EAF stopped loading. I've tried copying the contents of the rules.d folder from the stable version to the nightly but still no focuser loads. Jo mentions that this procedure brings his filter wheel back to life.
To answer your request, here is the result:
brian@nanopct4:~$ apt list --installed|grep asi
WARNING: apt does not have a stable CLI interface. Use with caution in scripts.