Can anyone recommend any material on accumulation and /or distribution please
Wykoff is one of the founding fathers of accumulation/distribution. He is no longer alive, but his methods live on. There are several free (and paid too) resources here... https://www.wyckoffanalytics.com/wyckoff-trading-resources/
Here's a freebie from the site which introduces Wykoff methods...
https://www.wyckoffanalytics.com/wp.../Wyckoff-Method_Wyckoff-Analytics_english.pdf
Additionally, VSA (Volume Spread Analysis) methodology was popular for many years. Of note, is that VSA (Volume Spread Analysis) survived the curse of trading method popularity.
Good trading to you!