Yes, Upgrade Pogoplug Mobile (or Series 4) from OpenWrt to LEDE - #9 by braian87b
Sorry, I did't see that you talked to me, you should add "@" previous the username in order to me receive the proper mention notification I think
if you follow the steps of qnology you first will have boot into debian on SD card. then using Debian you could configure pogo run OpenWrt from internal 128Mb flash, if you broke something on OpenWrt you could put again the Debian SD card again and reflash OpenWrt again, (I think that the uboot will try to boot from USB, then SD then internal Flash) ...
Worked perfectly on my pogoplug's mobile's, I did't try it to flash LEDE, but there is a PR on the new OpenWrt so the next release of OpenWrt (previously called LEDE) will have (again) Support for the PogoPlug Mobile/V4.
There is lack of proper instructions for people to follow, easily and securely, when we see a blog post from many months or even years and it uses really previous releases and even it have broken links (happen on qnology) or even many forum threads with a lot of chatting around with so many trial and error and go back and bouncing it is just too dificult to follow or even risky (There have been some bricks and I personally had that problem with old OpenWrt forum and Doozan Forums too on the past), I read hours even days, and finally just leave it there as is, and I have to read a lot of hours, several days too to install Debian on a Iomega Ez too. That is because when I managed to follow by myself I written that gist with steps and my notes about to help others to follow more easily (I did do for the PogoPlug Mobile/V4 and the Iomega Ez too.
I encourage others users that made success on these or other devices with newer firmware to write down their notes about too, in that way all of us will be benefited.