@cthorell, @fejd, I consulted @rainisto on this and he suspects that the reason for the MTD partitioning being incorrect on your devices might be an upgrade gone wrong. At some point the MTD partitioning scheme was changed, and when devices were upgraded to next PR level the MTD should have been partitioned accordingly but if there was some problem then the old partition layout could have been preserved on the devices. It is worth rtying to reflash the device clean back to Closed Mode with --no-preserve flag added on the command line, this should repartition both MTD and EMMC and fix the problem.
flasher -F main.bin -F emmc.bin --no-preserve -f -R