This is how you flash to eMMC easily

[gregb49]

@gregb49 where did you read you could "access eMMC memory by switching on and holding volume up"?  I recently got this device and am looking for all the informational resources I can find.  I'm in preliminary stages; haddn't read about that, yet.

I'm sorry but I cannot remember where I read that and I don't know what "tow boot" is. This is all a bit new to me.
I've used the Linux gparted/RPi Imager again to flash the phone the with Arch Linux ARM image and am persevering with that, at the moment, having typed in my calendar and contacts so far.