Comment 1 for bug 1792293

Confirmed, code defaults to
  /var/amavis/amavisd.sock
And the socket actually is
  /var/lib/amavis/amavisd.sock

$ amavisd-release --help
Can't connect to UNIX socket /var/amavis/amavisd.sock: No such file or directory at /usr/sbin/amavisd-release line 271.

But should that not be covered by the conffile:
  /etc/amavis/conf.d/25-amavis_helpers:$unix_socketname = "/var/lib/amavis/amavisd.sock";

It even says
  ## Functionality required for amavis helpers like
  ## amavis-release.

The main service reads that config, and I wonder if it might pass it along to the amavisd-release.
One that is more "pearl'y" than me might see that, but no matter how that is supposed to work it won't hurt to fix the default path.