Fast orange blinkup code

My imp001 (with Hannah board powered with 4 AA batteries) is blinking fast in orange (two blinks per second)
What is the meaning of this blinking code?
I cannot find it in the documentation (http://electricimp.com/docs/troubleshooting/blinkup/).

The board has been on for several days connecting to eImp server without any issue. I guess it is a “not enough battery” message, but I would like to doublecheck.
If this is the case,can you detect this situation in the electricImp device code and inform the server agent before the eImp gets disconnected?

Can you try changing the batteries? The hannah can read its battery level in software.

I kept forgetting to buy new batteries so I could not test it…
I have just replaced the batteries and it started working again:-)
Some documentation/code snippet about how to read battery level from software would be good.

For Hannah? Yeah, we should add that to the example code, it’s just a few lines…