Because the C6 buoys are plug and play, maintenance and repair...

Because the C6 buoys are plug and play, maintenance and repair work could be done ashore in a workshop. Simply disconnect the faulty buoy, replace it with a serviceable buoy and tow the broken one ashore.

Compare that to the Ceto 5 version, where a pump was attached to a hydraulic pod on the sea floor. Given the difficulty they had installing the hydraulic pods, removing them from the site would be a major headache if they required maintenance or repair work.