Discussion, talk and tips
https://forum.puppylinux.com/
The last FatDogArm release dates back to 16 April 2016:
https://distro.ibiblio.org/fatdog/web/arm-index.html
It looks like the project is still in beta.
Are there any further developments planned and a stable release?
The project is currently under cryogenic stasis.
That's a shame.
Considering the global energy crisis, there is an increasing demand for small computing devices with low power consumption and FatDog would be a cool OS to support that trend... 
Haha, don't get taken by the hype. All things being equal, same amount of computing power requires more or less the same amount of energy. ARM chips are lower-power only because they have lower computing power.
Less is more. The idea is to run a basic office desktop (browser + Libreoffice) at full HD resolution energy-efficient on ARM hardware... 