After upgrading my MNT Reform from IMX8MQ to A311D, I had to remove all my mods. I finally found some time to 3D print all parts so that everything fits again. Full description in the MNT forum: https://community.mnt.re/t/adding-lte-modem-and-other-usb-devices/1215/20
@josch
Really dig the Debian logo un the usb hub carrier board.
Where has the UART to USB gone though?
@vimja It turns out, that kernel and reform-tools and the whole boot process are so stable, that it has been a long time since I've needed any serial connection with my Reform, so it went away. When I have a new kernel or reform-tools release I test those on my other Reform motherboard (with LS1028A) and that has my UART adapter attached to it.