System prioritises keeping batteries charged over feeding ac loads

[angusemery (Angus)]

Am quite new to this but now live in the Algarve and want to make the most of the sun. Have started with a simple system: 6x400W panels, multiplus II 48/5000/70-50, MPPT 250/60, Cerbo GX and 2 Pylontech US5000C batteries. My aim is to use the solar during the day to feed my ac loads and top up my batteries. In the evening/night the batteries are used and if the soc drops to my minimum of 25% then the grid kicks in until the sun rises the next day. I have 3 phase coming in but only have 1 multiplus so am only dealing with devices connected to my L1 phase which includes all my critical infrastructure and heavier loads in case of power outage. I have BMS and am using the ESS assistant. Current setting is optimised without battery life, minimum soc of 25%, grid setpoint 0W, DVCC is forced on, SCS is on. However, when my inverter is switched to ON mode it prioritises battery charging instead of the ac loads. I get the solar charging batteries up to 100% and then the solar is wasted. If I manually switch to INVERTER ONLY mode I get the correct behaviour - solar feeds my L1 ac loads and any additional tops up the batteries. By sundown all L1 ac loads have been catered for and batteries are topped up for the night shift. Why is the ON mode not behaving like the INVERTER ONLY mode. I currently try to keep my system in INVERTER ONLY mode but at this time of year you get the odd cloudy day so sometimes have to switch back to ON to connect the grid. I have no schedules set. Any ideas, tips or tricks would be great Last point, am convinced it was working OK. Have recently updated VEConfigure 3 & ESS assistant but my multiplus is still at v508. V558 is available but was advised not to just update if things are working. Thanks