onAttach not called if backpressed during transition animation of next controller

Hi,
I use onAttach to tint statusbar per Controller.

normal behavior:
controllerB.onAttach
controllerA.onDetach

However I do observe this when I press back during transition animation

controllerB.onAttach
controllerB.onDetach

so my previous' controllerB onAttach doesn't get called (or any other callback on B), so I wont tint my statusbar, and controllerA's tint is still displayed

Its reproducable with any changeHandler, for example
```
RouterTransaction.with(controller)
.pushChangeHandler(FadeChangeHandler(2500))
.popChangeHandler(FadeChangeHandler(2500))
```

This seems like a bug, is it intended? Any workarounds please?