OK. I think I’ve resolved my battery life issues which seem to be directly related to having an SD card installed (earlier current measurements had SD card installed). When I remove the SD card then the idle current drops down to ~125 microAmps. Much better and should get over 1.5 years from a 2000 mAHr AA battery. That all makes sense.
Since there is no way to install as SD card with opening up the unit (I understand why that is necessary) I have just left it installed. Not anymore. You can either open the unit to remove the SD card or to replace batteries. Your choice!
Maybe it’s already there and I missed it but since this has such a huge impact on the idle battery life it should be clearly stated in the manual, app help page, etc. Even better to have a reminder notice if possible when the app is closed and the SD card is present.
Ideally the SD card would be powered off while idle but I assume that would be a hardware change. Something to consider for the future….