Problem is that with the current set up many users will be unexpectedly be locked out from the dead batteries, as there is no warning nor indication of battery running low. Yes you can still use the physical key but it defeats the purpose of smart door lock if you have to carry the key in the fear of dead lock. It seems that none of the suggestions and request has been made into the app or firmware. Battery percentage is still voltage value, which again is very confusing and counter intuitive, and to say 5months is expected range when you advertise 500 days battery life is misleading.
Here'd be my change request.
1. Change battery gauge to voltage, if you are unable to display correct capacity. Do not use % for voltage.
2. Give honest battery life expectancy based on average usage. Do not advertise just best case scenario. If worst is 5month and the best is 16months, let them know the range of longevity and pick the median so that people won't get caught off guard.
3. Add the number of turns as one of the usage data. Number of turns doesn't exactly translates to battery life indicator, but if my sesame died after 3500 turns at least I would know that under my usage condition the next 3500 would be my roadsign to look for. You could even add custom turn limit value so that the app would warn user when the number of turns approach the set value.
I think even with the current hardware limitation there should be ways to prevent unpleasant surprise.