Revit has four states relative to phases, New, Existing, Temporary and Demolished. There is no future state. What can you do if you want to indicate where the future phase work will be located?
Overlay views on sheets!
It is a simple matter to create a view whose phase is assigned to the Future phase and tell Revit through Phase Filters that you don’t want to see Existing, Temporary or Demolished elements. The building you draw in this future phase will look new. If you don’t want it to you can use visibility graphics overrides to make it look different or even much simpler.
As long as the scale of the views you need to overlay on the sheet are the same you’ll find that Revit will snap them into alignment. Here is a simplistic representation of all the phases on a sheet in two views overlaid.
This example is one that has a different overrides applied.
This is the Future phased view setup to put on a sheet.
If you look closely I've used the Linework tool to make a small wall that will be demolished between the New and Future work look like it is to be demolished.
Give er a try?