http://www.caa.co.uk/docs/33/CAP%204...21.1%20TSO.pdf
here is the new CAP413 including ICAO differences.
According to Chapter 6 for approach you just need to give Call sign, passing and clear level as per normal or just level and the information no QNH. In the UK
And QNH isn't passed by the controller until cleared to an Alt. So that looks like that one is taken care of in theory.
And to note most of the examples completely miss out ATSOCAS services
we can only live in hope that its a precursor for it being scraped.
Bugga just remembered ATCO's don't work to CAP413 do they?
They work to MATZ part 1.
So its revert to normal ops of wait until someone else books in and if it works for them copy them or make it up as you go along and when something works stick to it. As its more than likely CAP413 doesn't match MATZ part 1