I think, sad to say, that the question assumes too much i.e. "the coming demise' is not a given IMO. Much as i might be glad to see the end of 'the evil empire', i can only see it continuing for many years. It's very size, or mass, provides some sort of permanence.
I also don't see the GB sitting and planning such things; I really think they believe they are "God's organisation™" but I'm not so sure about them really believing they will rule the earth. Still I see that what concerns them is control ("over the Master's belongings"); demise doesn't enter into it for them.