In the UK, I believe it's specifically prohibited to use GP info prior to LLZ capture. Pity MLS never caught on.
That's like a NOTAM I saw recently about the runway center line lights being on test, do not use. I tried to turn a blind eye.
The GP info is very useful for descent planning sometimes. But that doesn't mean you descend with it below a cleared altitude or established on the LOC first. Any pilot knows that. So I've always found those remarks on the approach plates a bit silly that GP info cannot be used for reference before established on LOC.