Many thanks for your continued guidance. I hadn't considered that there may be a position that is even better though in hindsight a gun like this should be capable of single-holing at 25m. Something to try!
And yes the POI did move - by about 1.25 MOA at 25m - I have now re-zeroed it across all the ranges
The pressure thing is not something I have pinned down exactly yet. Starting from 200 it's good down to about 120 (about 70 shots) but then I seem to get the occasional low flier. Good enough for any competition though
Cleaning is also a much bigger issue than I realised. After a really good session with the rod a couple of weeks ago, it still benefits from a more normal clean (1 wet, 2 dry) after each shoot, and then half a dozen shots to settle it back in (sometimes not needed)
I think we're winning though