When the park applies for permits they have to be very specific about what they are doing. They wouldn't be able to just lump in a bunch of construction for a ride without it being explicitly applied for in a permit. We saw this when they applied for permits to renovate the HOS mazes. They applied for permits for both work on Frostbite and Demented Dimensions despite both of them being in the same building.Right - but in terms of building modification we agree there likely wouldn't be much assuming they keep the castle as is and don't expand or otherwise modify the shell. So minor permitting required might have documentation that could theoretically be submitted alongside other items requiring minor permitting.
Though your answer to that is that's not going to happen that way if they do put an attraction in that space.