I don't really see Mummy closing in the 2024 to 2025 timeframe. But I can see DK being the 2026 addition and Simpsons going down shortly before or after as they can afford to lose a single ride as they would have just gotten a whole new land/SNW expansion and guests will be flocking to it. Since all we have to work off of is a 2028 end date for Simpsons,
@Freak once mentioned over on the BTTF forum he thinks the 20 year contract would mean something like the opening date in May 2008 to May 2028. If that is indeed the case, they would want some new major addition in 2028 in time for the sheer amount of tourism that will descend for the Olympics.