EDIT: Solution in next post (this started as a question; yeah maybe I should have split it, but whatever).
Apologies if this is dumb question. I finally got my hands on some appropriate (64-bit) hardware, and ready to install software now.
I have read so many threads (in Kobol Club and elsewhere), Issues (at GitHub as well as Atlassian) and I think this is solved by now (on Armbian) but cannot confirm?
Official install instructions (on OpenZFS website) don't