We ordered the BP2000 along with the B2000 expansion. The system performs as expected; however, Oukitel does not currently provide an API to integrate the battery with Home Assistant.
I hope a future firmware update will address this by adding even a basic web server that exposes JSON values for essential data. If implementing an API is not feasible, it would be highly appreciated if Oukitel could share the characteristics_uuid and service_uuid for Bluetooth BLE. This would allow users to retrieve the values via ESPHome Bluetooth proxy and integrate the battery with Home Assistant in an alternative way.