Pinephone - likely long term support?

[tllim]

I’m on board with the privacy and security arguments in favor of a (non-Android) Linux phone. That alone pretty much guarantees that my next phone won’t be Android..  

Another aspect of Linux that appeals to me is that it is more environmentally friendly. Rather than forced redundancy when the manufacturer of my devices decides to stop providing updates (bigger issue with phones than laptops/pcs), I can keep running Linux for much longer – thus reducing resource consumption, landfill etc. However, as relates to phones in particular – my understanding is that ARM devices often have custom kernels. Many of the distros for Pine SBCs have custom kernels rather than mainline Linux kernels.

So.. at long last, my question: is my understanding about custom kernels correct, and if so what does that mean for long term support for a device like the Pine Phone? (Of course, I hope Pine will be around for a long time!) I suppose, being open source there could well be community support for as long as people with the know-how remain interested..

Most of the PinePhone OS based on milineline Linux kernel.