[noggin]

Thanks for this - will do some reading.  Presumably this works with your LibreElec builds as well as CoreElec - or do you recommend CoreElec now?

I will have too have to do some reading too.

AMLogic Android Dual boot LE / CE devices I believe have their closed source u-boot stored in internal eMMC storage.
It's why command line modding and dd writing of a new u-boot has to be carried out.

Not for the faint hearted, and you really want to make sure you know how to backup the original u-boot (bootloader) using something like TWRP recovery first. 

Yes - though I didn't know TWRP worked at that low a level.

It's infuriating - as the Minix U9-H is amongst the best solution if you want remote power on, if it weren't currently (unless you do bleeding edge) an unusable pain with other CEC devices (i.e. you still have to get up and pull the HDMI or power cable).