This thread kind of fell asleep after the new firmware came out. But the new firmware is like duct tape on a broken pipe.
A battery with a sagging voltage won't trigger auto-land as early as it did before, but it will still run down much too quickly. Both of my batteries with this problem last about 8 minutes before the percentage of battery remaining rapidly drops from >50% to <10%. So DJI has not fixed the problem.
I think the new firmware is actually a little dangerous. Instead of going into auto-land when the voltage gets low, it keeps going and next thing you know you're at 8% battery and 100ft up.
People who see <10 mins flights and/or a sudden drop in percent remaining should still register their batteries here. Any new batteries I buy for the P2 will be Limefuel batteries.