Its possible for the OS on your Series 1 to fail, we chose to boot from the SD card so that you have a way of fixing this.
You will need the following things:
The image here:
Software to burn the .img to an SD card, we like:
A sutible 16Gb micro SD card
An adapter or suitable slot on your computer (so you can write to the SD card).
Download and uncompress the file.
Open etcher, select the .img, select the SD card.
Hit the flash button.
Once the process is complete, simply put the SD card into the BeagleBoneBlack's SD card slot and turn the machine on.
The machine will now boot and appear as Series1-repair.local (and will default to AP mode unless connected via ethernet).
We are working on an updated version of the OS that will let you change the serial number and we'll update this article once we have released it.