Yeah, it’s actually way more complicated than you’d imagine due to the filesystem change.
I’ve written this article for exactly one reason: When I started this task, there was zero information about how to go about this. So this article is what I wished I had available but hadn’t. I’m a bit hesitant posting this here, since it’s so extremely niche (and it only gets more niche with time given the age of OpenWrt 15), but I hope that at least one person stumbling upon it will find it helpful.
That’s exactly why you should post it. Thank you for documenting it!