The way I was told during my CPL (allows privileges of an IMC - I never had a UK PPL let alone IMC) the legal minima were the same as for an IRed pilot - i.e. what you quote. The recommended minima were somewhat higher, and it might be considered foolish to ignore CAA SRG recommendations.
However, I have been corrected here on this before, so would like a definitive answer with reference if anyone has it. I have given up trying to find information in CAA online documentation. This will allow me to speak with authority if asked once I am a flying instructor.