Repeater Group IsLoading not changing

On a fresh page load a repeater group IsLoading works fine.

However, I have noticed today while working on this issue http://forum.bubble.io/t/detecting-repeatergroup-data-change/6177 that the IsLoading remains no if the data changes when a drop down options value changes which is part of the source statement query.

Is this by design or a bug? Given that the underlying source criteria changes sound like a bug to me?

Thanks.