After running for days, with restarts to add more debugging, etc. I had it running for more than 24 hours when I woke this AM to the board not running the test. As I recall, it responded to one web click and then didn't do anything more. But when I went to reset it, nothing happened. Powering it down and restarting it didn't do anything. Even the little blue flash from reset wasn't doing anything. It no longer appears as a port in the Arduino IDE. And when I power it with external 5V (Vin) the blue LED near the antenna stays on.
Any idea of what might explain this behavior. My concern is that somehow the software did it, overwrote something. Is it at all recoverable?