Building Pine64+ server image for ubuntu bionic/4.x kernel

I've been building armbian xenial images for my pine64+ a few times now and it works well. But I would like to switch to bionic if I can. I find it hard to find a good place of documentation for either the 4.x kernel or ubuntu bionic for armbian, specifically for A64/Pine64 boards. If I google, I see tons of forum posts with specific issues, but no coherent overview of any issues with 4.x kernels? And reading through 2-3 years of replies on some threads is a bit much to find the info I need. So what would or wouldn't work on a 4.x kernel on ubuntu bionic? Also, I am confused about who does what, and therefore where to go with problems. How are longsleep or sunxi involved in this? In the end, I guess my main question is: is it feasible to have a pine64A+ running no Ubuntu bionic, which I assume requires  4.x kernel, and what problems am I likely to encounter, or do I need to solve?

Cheers,

Dolf.