As in the case of SBCX-TN-004, the root file system was stored on a partition (<code>mmcblk1p2</code>) of the microSD card inserted in the slot J26.
<pre class="board-terminal">
armbian@Mito8M:~/devel/pmbw/pmbw$ lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
mmcblk0 179:0 0 7.3G 0 disk