How a sensor would work in the fuji sl/s series

I currently own the HS20, which I use mainly in EXR dynamic range mode. Sometimes I use the EXR SN mode where the sensor combines adjacent pixels, so that each of the larger 8m pixels lets in twice as much light. The new SL1000 and other new S series cameras have 16m pixels available, and no EXR modes. If you set the image size to 8m pixels in these cameras would it combine adjacent pixels to increase the light per pixel, or would it simply cut out half the pixels to reduce noise?

Thanks

A