The new hub will download all the site's data from the Livicom server: lists of devices, groups, scripts, users and site's settings will be restored.
The replaced hub will be returned to the factory settings: it is going to be returned to the state in which it was when it was first turned on. All data about bound devices, site users and scripts will be permanently deleted.
You can disconnect the replaced hub from the Internet and from the 230 V mains, or you can register it in the Livicom app as a new site.