Pylontech questions. BMS - SOC% - Firmware

[SimonSays]

The issue of the older battery going below 10% was resolved by discharging to only 15% SOC.

What I was getting at was that battery tolerates being discharged to 10%. Another user mentioned that, being an older Pylontech, it shouldn't be discharged below 20%. It's clear that battery tolerates being discharged to 10% but alarms below that, so I think the 20% limit is a red herring.

The wiring is exactly as per Pylontech manual using supplied interconnect cables.

I still think that battery is being worked harder than the others in the stack, and probably has a lower resistance path, hence the question about cabling.
Just one stack and one set of DC cables going to the inverter, and the positive and negative are at opposite ends of the stack?

[knighty]

photo of your setup/wiring?

are you happy poking around inside? - maybe drop it down to 10% soc and then check cell voltages?