AC / Low Battery help

[zalusky]

The Silicon Valley area recently had a large multi day power outage starting on a Tuesday around noon. A number of things happened and I am looking for suggestions for the future.

First off the system behaved as it should and went to battery backup. EVL does not show any AC loss alert.
My network eventually failed as the UPS ran out of juice after a few hours.
At that point the EVL reported a network supervision error.

Our utility company had not ETA for multiple days eventually they indicated restoration around Saturday.

The battery backup was performing and I kind of forgot about. We armed the system as we were going out for lunch and dinner.
On Wednesday (I think) we returned from lunch and the alarm was going off. I went inside and my graphical keypads were reporting low power and just blinking and unusable. I went to the 6160 keypad and it was not responding. The alarm was doing its job and very loud.
My panel is hidden behind a lot of stuff on a shelf which I had to clean off and I was finally able to pull the battery leads and stop the alarm.

Our power was restored on Thursday evening and the backup batteries fully charged up and the error messages went away.
Interestingly enough when power was restored the system was in away mode so it recovered the last mode it was in. We were in the house and had to disarm the system.

The EVL notifications showed everything once power was restored like network restoration / low battery / AC restoration and finally battery restoration.

Searching the web people say when the power failure happens if you know its for an extended period of time you should disconnect the backup batteries.

So my questions are more broadly for the Vista 20P people:
1) Why was the siren able to sound but my 6160RF keypad non functional.
2) What do I do when I am going to go on vacation and be gone for an extended period of time and a power failure occurs.
The alarm will sound annoying the neighbors and I can't disconnect the batteries.

3) Is there a better forum to talk about power failure scenarios.