Font Awesome fonts not rendering after Edeliver deploy

They are showing on my dev mac but not on my staging or production servers.

On the dev mac:

brunch-config.js

  // Configure your plugins
  plugins: {
    babel: {
      // Do not use ES6 compiler in vendor code
      ignore: [/web\/static\/vendor/]
    },
    copycat: { // copies to priv/static/fonts/
      // "fonts": ["node_modules/bootstrap-sass/assets/fonts/bootstrap"],
      "fonts": ["node_modules/font-awesome/fonts"],
      verbose: true, //shows each file that is copied to the destination directory
      onlyChanged: true //only copy a file if it's modified time has changed (only effective when using brunch watch)
    }
  },

Can anyone suggest what may be causing this?