Last time I worked it out the current draw in sleep mode was on avg between 50 and 100uA. I need to work it out again, sorry I can’t remember where I put that figure. The main battery draw is waking up once/second to send out a radio packet. It worked out to about 2 years assuming a 2000mAh alkaline AA battery.
I haven’t run the figures for hibernate node, but I’m pretty sure it would hibernate for longer than the shelf life of the batteries.
The meter can measure its battery voltage and the iOS app displays it, that feature is still missing from Android though. When that’s added we can hopefully get some more insights on battery life in the field.
Re: LED location: In the beginning the plan was not to make the case transparent. This meant having the LED close to the surface was a good thing, and having it pointing straight back seemed like a bad idea, and I was trying to keep as few components as possible on the front because I wanted all the SMT done in one pass. If this gets revised the LED will move.