You can always rely on UK parochialism on this site!
Fatfish - you would do well to steer clear of various websites that think that they know the subject and go to the authority - in the absence of any equivalent document in your own state that might have slight variations (I see you quote Singapore), then it's ICAO Doc 9432 Manual of Radiotelephony. Although there is ongoing progress to standardise the UK procedures with those of the rest of Europe and ICAO, there are still many UK-specifics in CAP413 and it is just not an appropriate document for use outside the UK.
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