I'd say demo should start right away. Every day that whatever hotels they build there aren't done is just money lost to other hotels. It's direct loss of income, unlike rides. If those are put off, it's not necessarily lost income.
Even if they don't plan on building immediately, I'd really expect demo to start as soon as possible. The crews that do that wouldn't be the ones that would be tied up building the other projects. There's money to be made on scrapping support structures and anything they are going to sell off. And getting it cleared out now also allows them to start building whenever they are ready to build.