I have a 12v lead acid battery that I drained to 50% SOC but when the charge controller starts charging the battery it will increase the SOC normally until the charger makes the battery reach 13.20v while current is going into it, which makes the SOC jump to 100%. I know the battery isn't 100% SOC because its still undergoing the bulk charge and hasn't touched absorption/float as it normally does.
I assumed since the BMV does calculations with amperage for discharging to determine that actual SOC instead of relying on voltage, that it would do the same with charging.
Also I could have the BMV configured incorrectly so if there is something I should change in the settings let me know.