Reg 530.3.4 which references Annexe ZA of BS EN 60439-3, will be changed to say, Annexe ZB of BS EN 61439-3.
The 61439 series has & is replacing the 60439 series.
Obviously references to 60439 elsewhere will also change.
I believe the intent of the proposed reg 421.1.200, is to ensure that consumer units used meet the requirements of the relevant product standard, by re-iterating the heat/flammability requirements.
Also, as the UK deviates from 61439-3, via Annexe ZB, it reinforces the safety of our National deviation from the International standard.