Hey @Sergey Lepeshkin, your information proved very helpful! I have a tv box in the same vein as yours, but mine is version Z01S-V13.3, so they probably revised it a little bit.
Thanks for finding the UART pins! I will try it out and post what I find! My objective here is to overclock it, install active cooling and a heatsink, and see how it runs some emulators.
Btw, quick question, performance wise the box would be faster on Armbian or Android? Thanks!