Ok, Lexus have said the recall work was carried out in August this year for the Valve Springs, so in all likely hood I suppose they not set the timing correctly or something along those lines...
The question is how to get a local dealer to correct this issue (recall work was done 200 miles away - though I guess I could return it there if absolutely necessary), and whats stopping them charging me for a diagnosis and then claiming the error code is caused by a fault with something else that is not connected?!