Hi darrenortsman,
You don’t have to buy a second license. You can use the plugin on both domains and use the license on whichever one you choose. BUT, the one without the license will not have the auto-update feature. You’ll have to manually upload and install updates there. As long as you have one active license though, you can grab those files from the Account Central > Downloads link that you see at the top of the Forums pages. And you’ll still have support here in the forums as well.
Does that make sense?
– Julie