Hi,
First of all, I m new here but it is not the first project here btw. I m working with another czeck company here. As I understand, you would like to config image file, I m wondering what type of feature you would like to add it? The android should be recompiled with its recipes (bsp). I have strong knowledge on Yocto and linux, u boot compiling. Morever I also have banana pi scb having A20 processor I can test it what I have builded. If you interested in, please let me know.
Best Regards