Only the manufacturer can answer this question directly. On the smarthomeassistent.en page you can only read the following: "Compatibility with the Roborock S8+ suction station still unclear. As of today, the suction station is not sold separately! In my opinion, it is not worth buying an additional suction station at a later date, as this will be much more expensive than a combined purchase (S8+), if it does become available at some point. In addition, the water tank has to be refilled after approx. 150m2 , so emptying the dust container is no longer a big deal...