Load custom dtb files on IOT-GATE-IMX8PLUS

Hi,

As asked in this post, I would want to be able to load a custom .dtb on an IOT-GATE-IMX8PLUS, but from what I gathered, we need to build a custom balena image to do so. The current balena image provides 3 .dtb files iot-gate-imx8plus-m2tpm.dtb iot-gate-imx8plus-usbdev.dtb and iot-gate-imx8plus.dtb.
It would be very helpful if we could load any of them through a config.txt file, or the extra_uenv.txt file.
It does not seem to work for now.

Best