I have two almost identical systems with Multiplus II 10kVAs and 60kWh battery banks made up of 4 x 15kWh Cyclone batteries (made by MeritSun and register on the system as Pylontech, I think they use or clone their BMSes). I'm using the batteries' BMS over CAN, a Cerbo GX with ESS assistant, two Smart Solar RSs and each system has a legacy AC coupled grid tied inverter too.
I've just gone through a few days diving into Node Red on v3.34 (not relevant to the behaviour hence leaving this post in general questions) to automate setting the ESS mode to Keep Batteries Charged when the SoC gets close to 100% because it's the only way I can get the solar charge controllers to stay on and let the batteries balance after the first battery reaching 100% triggers a high voltage alarm - it's worked fine to keep it in that mode for a few minutes to let the batteries catch up to each other and all decide they're 100% but if I don't do that from time to time an ever increasing gap builds up between the SoC of the constituent batteries and this ends up having serious financial consequences on the effectiveness of the system as a whole, especially when running Optimised with BatteryLife which is my preferred setting.
So this behaviour and automation are working great on the one system but now when it comes time to make the other system follow along the Cerbo GX code version has gone up to 3.40. Now whether automating or manually I simply cannot override things at all. It gets to a high voltage warning (NOT alarm) and then forces Keep Batteries Charged off no matter what I do. So now the only way I can see to narrow the gap is to manually switch batteries on and off all day to let them catch up to each other which is simply not practical for me.
Is there anything else I can do to get the same result that doesn't involve forcing the version back to 3.34 and staying there indefinitely to avoid the new "fix"? How does one persuade the powers that be that this is a bug/needs to be changed back?