As far as I know nothing has transpired Re this study.
Atlas biomed did my gut biome test. They seem good
Atlasbiomed.com

I have been trying my own resistant potato starch study and believed it may be helping the arthritis in my fingers although this could also be the result of eliminating sugar from my diet.
Unfortunately I have been experiencing unusual cramping in my left arm & now my wife who has been taking a teaspoon of “potato starch” is experiencing similar cramping???
This leads to my main concern…. Here in Queensland Australia I have bought several bags of Lotus Potato Flour that have the word STARCH clearly under the word flour… I have also now discovered that there is a clear distinction between potato starch & potato flour… Lotus also have a similar packet stating potato starch…. how can I find out if this is still potato flour and has anybody else experienced muscular cramps

Hi Marshall
To the best of my knowledge the easiest way to tell them apart is that potato starch (the one you want) is a pure white fine powder, potato flour is slightly courser and cream/beige in colour.
Hope that helps