*.sg.pressero.com resolves to our Singapore server.
You can assign anything.sg.pressero.com as a site URL in the Domains tab. If you try to assign a URL this way and see an error, that prefix may already be in use and you may have to choose another prefix for that site.
Please note that this information applies to users in Asia and Australia who are located on our server in that region. If you login at admin.pressero.com normally, you will not be able to login to the server listed above, and the above site domain and routing information does not apply to your account.