Hi @eliot . This https://github.com/resin-os/meta-resin/commit/7a39577e0a36427e82efeab9a57b609f2c0e7c38 should make it that it won’t try to install on your USB stick from which you are booting.
If it’s the case that on your board the USB device is detected as sda and the internal media is detected as sdb, then you would also need to change https://github.com/resin-os/resin-intel/blob/master/layers/meta-resin-intel/recipes-support/resin-init/resin-init-flasher.bbappend#L3 and add “sdb” there too.
Can you double check please that in your case the USB stick is detected as “sda” and the internal media is “sdb”?