Not sure what to suggest, but if they're not using the Nordic bootloader then you could try commenting out the bootloader:1 line in the BOARD.py file? That'll ensure that there's no bootloader built into the image, which may help.
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Not sure what to suggest, but if they're not using the Nordic bootloader then you could try commenting out the
bootloader:1
line in the BOARD.py file? That'll ensure that there's no bootloader built into the image, which may help.