I'll get the ls -l output later today or tomorrow.
As you can (kind of) see from the DIR command, the files are symlinks and within a minute or so, the symlink is not shown even though the file timestamps remain unchanged.
What would you consider "relevant Docker settings for the location". The Docker settings on the /live/[domain] folder where the symlinks are disappearing are (AFAICT) the same as the /live folder where I've created symlinks to the same target that have not disappeared.
Is there something in particular in the Docker settings I should be looking for?