Hi Jerod, I hope you're doing well!
The FreeRTOS APIs can be used to develop and implement BLE applications, as well as the OS Abstraction APIs.
Most of the provided SDK BLE stack examples provide both implementations, either using FreeRTOS or baremetal with OS Abstraction implementation.
A good starting point for developing with the BLE Stack implemented in this device in conjunction with FreeRTOS could be the BLE Beacon example.
It can be found in the following path of the SDK:
<…SDK_2.2.1_QN908XCDK\boards\qn908xcdk\wireless_examples\bluetooth\beacon\freertos>
Please let me know if you need any more information.
Best regards,
Sebastian