P300 doesn't use the SmartMesh protocol. It is a Fixed Wireless Acces (PTP/PTMP) product. Therefore the RAP/MAP/eMAP terminology is not relevant.
In P300 there are 'Root Bridge' and 'Non-Root Bridge' roles. In the case where you need a multi-hop link, you would need to deploy back-to-back links with different SSIDs and the A-link Non-Root connected to the B-link Root with an ethernet cable.