Recently I downloaded the 8.6-IoT image from your website and after I flash the image I am able to log in the console for the first 10 seconds over the usb port then after that I was unable to log in any more.
I tried other Debian images and this always works. I only seen this issue on the Debian 8.6-IoT image so far. Wonder if I can get some help from you. Seems like there is no dhcp request on USB0 port.