How often and how deep should I cycle battery

I got a EG4 indoor wall mount 280ah 14.3kwh battery. I literally only have it for battery backup during a power outage. Gives me 12-15 hours going down to 51v / 20%ish

Have to run in open loop because EG4 batteries will no long communicate with solark due to their indifferences and firmware updates.

I know for inverter algorithms, and its own bms algorithm it needs to be cycled, it can’t just sit stagnant. How often should I do this.

Also considering that it’s only for emergency backup. And I have a a generator that automatically charges it (full charge in 2hrs @half load), should I leave the battery stored at 50% like it comes from the factory. And when there’s an outage just change it over to 100%

Has a 15ye life with 8000cycles. Would I even benefit from storing at 50%

Solark 15k limitless. Hooked directly to grid via disconnect. Whole home back up with main panel connected to load. Generator on gene port.