Cope with growth by dividing the team along role-based lines
Find clusters of roles that have strong mutual coupling, but that are loosely coupled to the rest of the organization. Form a separate organization and process around those roles.
A large team becomes hard to manage. Organization patterns that suited a smaller team might not suit the larger team. A regular hierarchy could grow readily, but a regular hierarchy does not distribute responsibilities evenly. In many ways this is orthogonal to ConwaysLaw, which probably should be considered first.