emm

I can't find the manual for your model now,but previous Pylontechs were fine with User-defined voltages
If you had used a LA setting on the inverter you would switch to USE,set the minimum float and bulk voltages,charge amps and be done pretty much

They likely mean USR mode aka Voltage specified,which works for most lithiums as their own BMS will generally tell you to f*off if you try exceeding their ratings

If it is this inverter then it should work - it has comms capabilities via CAN and RS485 which the pylontech supports. It may be that the firmware does not recognise the battery but in that case you can run it using Voltage / user mode using the voltage settings supplied by the pylon manual. You SHOULD be fine. No need to throw the baby out with the bathwater