The way it's build--FFB is designed, constructed and made far away from the concourse (I guess that makes more sense) of Springfield when it was constructed; as it not only acts for FFB on cooking and food prep, but also for Three Broomsticks. I don't know how the restrooms were, as they were designed and made in 2012-2013; but I have to imagine that's been reinforced.
Duff Gardens, P.Q.Butterfats, Luigis, and Sud's should get reinforcement and upgrades with the construction of Hollywood Drift in the term of it's grading. In the leaked art, they also have backup plans if things fall with the IP, preserving the food locations to be simply rethemed if that time comes.
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But to piggyback; I genuinely think there is a real scenario to where Hollywood might actually keep The Simpsons. Doesn't hurt Disneyland Resort, promotes the IP as Fox/Disney continue to invest into it with the multi-seasonal rollout of the show, and merchandise wise I am willing to bet Disney and Universal are happy with it. Plus, the brand itself isn't hurt (Even if it is on the older side).
It feels like a unique situation for Hollywood IMO due to how baked in Springfield is to the core infastructural design of the Upper Lot, due to the Three Broomsticks connection and how it's gonna get boxed in by Hollywood Drift. Add in the infastructural overhauls that could require things to happen sooner.
If TWDC and NBCUniversal can come together and tackle overhauling The Incredible Hulk and allowing Universal Creative to give it a fresh leash on life; I actually think Hollywood may be a possible contender due to the infastructure of the area and how much change is already going to be needed with Hollywood Drift.