What did you end up paying in the end?
Was it classed as a 16K service with valve clearances, or was it just done as an annual service.
Mine is due service now (2 years 12k miles) and I have two Main dealer quotes.
£260 from Dobles and
£530 from Norton Way reduced to £99 when they realised it hadn't reached 16k.
So from these prices I don't think they treat it as a 16k service.