Each Single Site license can be used on one URL at a time. This includes sub-domains, sub-folders, http, https, www, etc.
So if you want two URLs active at the same time, you would need to have two Single Site licenses or a Multi-Site license.
That all being said, a URL that begins with the following does not count against the WishList Member license total.
For local host sites the following examples do not count against your license total.
This means that a development or test site can be set up and does not count as a use of a WishList Member license.
The WishList Member license key and email address must still be used to activate the test/development URL, but it will not count against the WishList Member license total.
This will allow for testing on the test/development site while the live site can also use the WishList Member license key.