It seems the pre-loaded with OpenWRT routers have been mentioned before, including the one I have, Kasda KS6512 (I also have some KS6515, I believe, in the other room). The chipset is supported, and openWRT comes pre-loaded, although if I install their Linux 1.3 upgrade it goes away and is replaced by something I can't ssh into.
With the ones I can, I'd like to be able to use my ability to access the device to get what they do to make it run on their gear (any 'magic bits' etc) and contribute it back, so a non-suspicious open source option can be made available. I'm willing to do the work here, but it seems the concept of ripping an openWRT pre-loaded device to reverse engineer it has not been previously documented. Or at least not in a way I'm able to locate.
When I connect I find that it might be possible to find the MTK OpenWrt SDK and go from there, but I'd like to make a backup before I brick a unit.
BusyBox v1.22.1 (2017-04-20 11:10:08 CST) built-in shell (ash)
Enter 'help' for a list of built-in commands.
_______ ________ __
| |.-----.-----.-----.| | | |.----.| |_
| - || _ | -__| || | | || _|| _|
|_______|| __|_____|__|__||________||__| |____|
|__| W I R E L E S S F R E E D O M
-----------------------------------------------------
BARRIER BREAKER (Barrier Breaker, unknown)
-----------------------------------------------------
* 1/2 oz Galliano Pour all ingredients into
* 4 oz cold Coffee an irish coffee mug filled
* 1 1/2 oz Dark Rum with crushed ice. Stir.
* 2 tsp. Creme de Cacao
-----------------------------------------------------
MTK OpenWrt SDK V3.4
revision : benchmark : APSoC SDK 5.0.1.0
kernel : 144992
-----------------------------------------------------