Since the group can potentially contain 15 members, excluding the three leaders it comes out to 12. Those 12 will be split into 3 groups of 4, and each leader will have authority over the ninja in their group. Here's how we picture it.

Uchiha, Saya

Sakana, Umi
Sabakuda, Ryuga
Moon, Phoenix
Chiyuki, Tennin

Uchiha, Kazune

Yajuu
Hyuuga, Ka
Seiza, Rusou
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??? (Orochimaru's daughter)

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