The dealers now seen the video I sent, and just phoned (great service even out of hours)
It appears the rollover valve needs to be repositioned with a longer piece of pipe.
This apparently is more common with the 4/4 Sport due to no spare wheel, where the inner plastic luggage tray is in contact with the roll over valve, stopping it to breath / release air.
A new pipe will be ordered then a trip back to the dealer and get fixed. Result 👍
