I will make a case against being able to modify SBL or partition tables from the phone in general just by being root. There should be one more layer of protection.

I have been through many of the XDA resources along with some android unbrick blogs - they all rely on the provided images. I have yet to see a 'reverse engineered' effort succeed reviving a phone with some frankenstein image.

Citation from a comment I received on the following resource by androidbrick: http://www.androidbrick.com/ultimate...oad_qpst_qfil/

"Thank you so much for the kind words. As to your problem : Qualcomm 9008 port is simply just a “service port” that waits right files from you to wake up the device. Just a commication port, you cant manualy flash anything over it. You need a proper service rom that includes ““rawprogram0.xml”, “patch0.xml”, “prog_emmc_firehose_XXXX.mbn” or “MPRGXXXX.mbn”” in it, without those files your phone cant come back sorry. Those mbn files are a must to turn your bricked phone into EMMC mode again (Qualcomm 9006), so your phone’s EMMC drive will wake and accepts your backed up partititons again from linux or from an other windows based partition software.. So you just need to find those, or nothing can be done, sorry. Greetings."

So for now that means we (I) need to switch from Qualcomm 9008 (service port) to Qualcomm 9006 (emmc mode) requiring:

- rawprogram0.xml
- patch0.xml
- MPRGXXXX.mbn (as at least Jolla C listens to Sahara protocoll, not the supposedly newer Firehose protocol)

And I don't even think that the .mbn file is the actual whole ROM, in our case SFOS but just the part needed to revive the device. Does it include anything that falls under NDA? Who can tell.

That's our situation, judging from the dead Jolla 1 thread.