The Joulescope JS110 will uprange on overflow (like 180 mA to 2 A) very quickly. The downranging on underflow is intentionally much slower to help account for this effect, which happens even with DC signals, such as square waves.
For your 10 Hz signal, the JS110 will definitely downrange at the zero crossings. This is fine, but from an audio perspective, the signal will have higher THD than if you manually set a single fixed range. For your 50 kHz signal, I am not sure that your Joulescope will ever downrange from the 2A range. For some more information, see this old post which prompted us to improved the DSP applied to range switching.
For true, single-frequency AC signals, you would ideally want the instrument to autoranging on the amplitude and ignore the zero crossings. Alternatively, it could detect the lowest frequency component and adjust the downrange time accordingly. The JS110 does not have any features like this, so it will have more range switches that would strictly be necessary.