The increases in DH/MDH which you learnt when you did your IMC rating were, and always have been, recommended, but not legal limits. Chuffer's quote confirms this. I think you will find the recommendation somewhere in the AIP (not the ANO), but it is not mandatory. The minimum viz, however, is mandatory.
As for any recent changes, I don't know of any, and I have no idea what your CFI is talking about.
FFF
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