Premium is a subscription-based model to support the bot while getting more features.
There are two premium tiers: Premium and Premium+. Both tiers unlock all the settings and commands, but Premium+ has fewer limits (it has unlimited Master Channels, for example). These limits are listed here.
If you are looking for how to enable premium in your server, see the guide below:
Once a user is subscribed to premium, they will be able to enable it on one or more servers they choose (1 for Premium, 3 for Premium+). When a server becomes premium, the user that enabled it is called premium provider of the server.
A premium subscription for a server is strictly linked to the premium provider's subscription; if the premium provider unsubscribes, the server will stop being premium.
A premium user can enable premium on one or more servers of their choice with the command /premium enable. The user will become premium provider of the server.
The server's premium provider or the server's administrators can disable premium for the server with the command /premium disable [server-id]. The premium provider will stop being provider for this server and will be able to enable their subscription on another server.
A premium subscription for a server is strictly linked to the premium provider's subscription; as such, it will become inactive if:
the premium provider unsubscribes;
the premium provider downgrades from Premium+ to Premium and the server exceeds the available slots.
If the conditions above stop subsisting, the server will become premium again until it is disabled.