I imagine it wont be long before all the cases are completed
What cases?
For battery life I never measure or count, it's always been enough for me. I'm not vaping hard all day tho.
Since its unregulated if your not camping or something I would recommend a multi battery charger (which you likely have) and just hot swap whenever you want.
With my use 1 battery almost always lasts me 1 day. I could push it into the next day, but the charger is a few inches away, and I would rather start tomorrow with full power.
Since batteries are so easy to change, charge, and acquire it's really no trouble to have whatever power you want in the moment.
Overall without numbers the battery life of 1 battery is good.