The objective of the first stage is to bring the FCFs from the proforma to time0 for the discounted FCF.
For stage two, you use the growth rate to find the FCF for t+1 (lets say yr 5) and calculate the present value (at yr 4) as if it was paid in perpetuity, using “Adj WACC - Growth” as the discount rate. Remember, this is the PV at year 4 so it must be pulled back to like-terms by bringing it back to time0.
I guess itd be possible to bring stage one to time4 then calculate stage two at time4, then bring both back to the present value at the same time but that seems like a lot more work with a higher chance to make mistakes.
Is this what you were asking or did I misunderstand?