Backhaul (point-to-point) nodes can share the same channel as downlink/uplink nodes (point-to-multi-point).
Working example:
 There are 4 nodes sharing the same channel, 165@20:

• KE8MVM-LHG-XeniaNorth-MVHS (backhaul)
• KE8MVM-LHG-MVHS-XeniaNorth (backhaul) colocated with NC8Q-Centerville-Bellbrook
• NC8Q-Centerville-Bellbrook (downlink) colocated with KE8MVM-LHG-MVHS-XeniaNorth
• N8NQH-to-MVHS (uplink/downlink)

The point-to-point backhaul can maintain its function and
the point to multi-point can maintain its function.

Sweet!

73, Chuck