Hi there Allison, thanks for reaching out!
You can use actions and hotspots to achieve this: First, make the current state layer invisible and the future state layer visible. Then drag a new shape onto the canvas > right click > Add Action. In the panel that appears next to the shape select “Toggle Layers” and select both layers (future state and present state) and click "Done". Now, when you use ctrl+shift+click (cmd+shift+click on Mac) on this shape, both of the layers will be toggled to the state they are not currently in, meaning the future state will turn invisible while the current state will turn visible.
Hope this helps!