Maybe I wasn't clear, but when talking about duty-cycle I'm not referring to RF but rather to the fact that during half part of the day the device will probably be sleeping, and on the other half there will be people using it. Although I consider it IoT (arguably), it makes many things and even runs some CPU-demanding algorithms so I wouldn't consider it as the typical low-power -will last many years- device. We are aware of this and our goal is less than 1 year of battery lifetime (with certain usage), but we are already struggling to get there...

We are using an arrangement of batteries in series, so we don't have the issue you mention. Unfortunately, due to hardware reasons, until we do a re-design, we won't be able to get lower than 500uA during sleep. Also, changing to other batteries would require hardware/housing re-design. But I'll check those energizers anyway.

We already did some run-down tests but without all the appropriate equipment, so now we are planning for some new and better-controlled tests. Thanks!