mppt vs pwm

The controller only maximizes charging in bulk mode. Outside of bulk mode is when the battery voltage is high enough that you are not loosing to PWM or so it seems. The bulk converter is still converting excess voltage to amps so you should realize a small increase in PWM charging too IF the battery isn't already tapering. The Isc of my panels is close to 10a but I can see 16a when the controller first goes into absorb or I pull a load in float.