The warranty period of DJI Batteries are 200 cycles or 12 months (whichever comes first).
But the real life expectancy really depends on how you use the battery.
If you don't discharge it lower than 25% regularly, store the battery for longer...
The moment you hit 200 cycles (you can see the cycle count inside the fly app, on the battery tab) it shows the permanent warning on the Fly App.
I'll continue with these bats until they start showing signs of degeneration on Airdata, and if...
Here is what DJI says about battery cycle:
"A battery cycle count is not the times that you charge a battery, but simply refers to the times that the battery consumption accumulates to 75% of the battery capacity. When the battery cycle count is...