The unlimited automatic updates applies during the year the subscription is in effect and means you can update as many times as wanted during that time. Automatic for WordPress plugins doesn't mean it will update without a user's input though. It will let you know if there is an update available and you can click to the update link and it will update for you with all that entails, but not until you click the link to update.
The license subscription gets a person the unlimited automatic updates and support found in the member's forums here for the plugin(s) you have/get and lasts a year.
The licenses can be moved between domains if need be. There is a license manager in the Plugins page for each plugin that shows which licenses are attached to which sites and can detach/reattach as needed.