phone call today from VWUK 'Customer Excellence' ...'advice from technical is that no warning is given on the fob or on the instrument panel if the battery is low......some models in the group have this but not yours.....but as you have it booked in I would still take it to you local dealer for investigation and Ill speak to you after'.
I'm starting to think a batch of cars somehow haven't got this enabled, I would have been more positive it was a fault on mine except for Kalimon who had experienced no warning as well.
So, no further forward and I guess it's only a niggling thing but what is spurring me on to keep pushing them is the differing answers I have had from VWUK.