So I was at a JW gathering today, and I over heard a brother telling a sister about these new changes. According to him, both one day circuit assemblies will be put together on the same weekend, one on Saturday, the next on Sunday. That way the assembly halls could be used to fit in more circuits as they increase in numbers. New halls means more people and circuits which means they will be able to use the same Assembly hall without the need to build a new one.
As for the Regional Building Comitee (RBC), I heard him say that the plan was to remove them and instead, make a departmant at that would be incharge of the construction of Kingdom Halls and Watchtower properties worldwide. Not just that, they will be building houses for missionaries (and I think full time pioneers or something having to do with pioneers) and have maintenance teams in charge of maintaining the properties and kingdom halls. He said that the brothers reporting this were very "giddy" as it was "the biggest change" in their history.
I also overheard something about having rescue teams during disasters. That brothers have their own equipment and such. But I couldnt hear everything so that's all I know.