Just had my 20k service done. Quite a list of jobs to do including: Valve clearances, Valve timing, plugs, fluids, fork oil change, filters and I needed new read pads. I was waiting 5 hours, so I assume it took about that long and cost was £670.
Probably would have been more economical to swap the bike earlier in the year but couldn't fit a change in the time available. Hey ho....

Still like the bike and the fork oil change is at least noticeable.