Did you try the reset button? I have never tried it but someone gave suggestions on how to use in the main S9 thread recently. It was something like, disconnect all the hashboards from power and from the control board, boot it up, hold the reset button for more than 10 seconds, let it reboot and wait 20 minutes. Go look for the exact directions though because I may be getting it wrong.
Close. (and it was me)
Power down, remove power leads from hash boards. Leave power leads connected to controller.
Turn on power, Wait a few seconds, then press the reset button and hold in for ~ 10 sec.
Release button and leave it alone. The red led by the lan port should flash a few time to tell ya it's resetting.
At this point, the older s9's needed maybe 5min at most. You should be able to log into the GUI and at least change your pool info.
With the B16 on up or when using an older s9 with this new auto-tune software -- not sure. With no hash boards to fiddle with and speed test I have no idea what the firmware will make of it. Hopefully like with the older miners and firmware it will just shrug its shoulders and finish setting up the other parts of the miner... Probably would be a good idea to see what the Kernel Log reports while it tries to find boards
Anywho, if you can get to the GUI and set pools you should be good to power down, reconnect power to hash boards, maybe slaughter a chicken or lamb, then power up and see if the gods have been appeased...