We don't allow changing smart URLs because this would mean our customers lose access to analytics we provide i.e. tracking notifications, views, distribution & growth and other many other analytics features.
Thus the Beaconstac app/dashboard does not offer a way to change the Eddystone URL. But you can use the Custom URL option to broadcast any site through Eddy beacons (if you don't wish to use pre-created cards or forms).
To set up a custom URL kindly follow this procedure.
You can read more about this on our blog.