The group that a prospect arrives at when they are initially registered is call their "Arrival Group". For prospects created via integrations with leads channels, the various distribution strategies configured by each channel will determine the Arrival Group.
For prospects uploaded manually through Zenvia Conversion, the Arrival Group will be the group of the user who uploaded the prospect
All prospects are assigned to a group:
When the prospect is created, the Assigned Group is the Arrival Group (as mentioned above)
When a salesperson takes on a prospect, the prospect is assigned to the salesperson's group
When a prospect is transferred, they are reassigned to the group of the salesperson receiving them
When we talk about a prospect's zone, we mean the zone that their Assigned Group is part of.