The difference between a user who is "registered" and one who is "uploaded" comes down entirely to activity. Simply put, if a contact has done something in the VoterVoice system, they are considered registered. If they have not been active in VoterVoice, they are uploaded.
A registered designation has no connection to data points such as address, constituency, subscription status, etc.
The one functional difference between a registered and uploaded contact is that a registered contact is considered to be in charge of their own information. Mass updates to your contact list will not change information that a registered contact has approved or changed when they took action. This is to prevent a situation in which a typo in your database is fixed by the contact and then re-introduced when you next updated your contact list. Fields that are NOT displayed on the user profile can be updated via a mass update to the contact list.
If you want to get a quick view of every registered contact in your system, just go to Search Contacts and perform a new search for "Contact Type / Is exactly / Registered." See the GIF below for more details: