NimBLE how to do directed advertising with RPA address

[steaky1212]

I need to have a BLE peripheral perform directed advertising to a central that has previously bonded. The central is a phone and is thus using a resolvable private address. How can this be achieved with the NimBLE stack? Specifically, how do I retrieve the correct address from the bonding storage to pass in as the second parameter to ble_gap_adv_start(), since the central is using an RPA?

Thanks.