I work for a new home builder. Occasionally we buy a "tear down" - a piece of crap house on an exceptional lot - which we demo and then build a 5000 sq. ft. home.
Demo is done in less than 48 hours, including completely clearing the debris. Up to two weeks if we are salvaging the bricks and selling them as reclaimed.
But the SWSA building was
not demolished—it is in the process of being remodeled.
Immediately after SWSA closed, they started taking out the figures. They then had to take out the ride mechanics, take down drywall, likely knock down some walls and put up new walls, have a structural engineer supervise I would guess, obviously re-wire, install bathrooms for the face characters and probably guests too.
PFH is bigger than PFF, and since it was remodeling versus building a new structure, I am guessing that these are two reasons why it took longer. Plus, they might be utilizing artisans from other parts of FLE, and hence their schedule might have depended on when certain aspects of ETwB/Mermaid/BoG were completed.
PFF is pretty much the lone big construction project at DCA post Carsland opening.
They just finished the Tangled restrooms, my guess is that this crew will work on whatever bathrooms PFH has for guests or castmembers, and the crew that put on the finishing touches may also be now moving to PFH. I am guessing that it is cheaper to hire one crew for a year, then three different crews for four months so that PFH, Tangled restrooms, could open with ETwB/Mermaid/BoG at the same time.