@nmaas87 thank you for the prompt response. I spent so much time thinking I was doing something wrong! 🤦🏻
According to this recent thread the OS can’t be downgraded without physically accessing the device - is this still correct? Presumably we’d need to use etcher again with the new image?
If anyone else finds this in the future, you can download the old OS with:
balena os download raspberrypi4-64 --version 2.75.0+rev1 -o balena_raspberrypi4-64_2.75.0+rev1.img
And the GitHub tracking issue for Pi 4 USB is https://github.com/balena-os/balena-raspberrypi/issues/710