So to get from the end of Philadelphia stage 2 (using this as a baseline due to most plans going for it) to stage 5, we'll need:
90*(2^3) + 90*(2^4) + 90 * (2^5) = 5040 progress
With +13 to Orbital rolls, that will require ~80 dice.
If we weren't to use any Fusion dice (extremely unlikely, as we already have 2), that would cost 2400 resources. But in a couple of turns all dice will be assumed to be Fusion dice, which would reduce the total remaining cost to 1200 resources.
If we dedicate only our current allotment of Orbital dice, it will take 27 turns, or 6.75 years to complete, or in other words we'll be finishing right around the time that Kane might approach us for the TCN.
If we dedicate 4 dice per turn, it will take 20 turns, or 5 years.
Hopefully the remaining +9 is stage 3, which will make things a lot faster.
In return we get +9 to all rolls, 2 free dice, 1 die in each area (9 dice total), and 20 PS.
It looks to me like once all dice are Fusion dice, that we are going to want to be throwing more than 4 dice at the orbitals per turn if we want to get to get both a fully functional Philadelphia and evacuate a significant number of our people before 1962.