Yes, I'll be as quick as I can, but I need to be clear.
There's a minimum size and you're going to dig that anyway, and once you're in there you have the options of making it bigger or not, depending on what decisions are made about committee rooms and where they're placed. It sounds like you can start digging without knowing the final size, because you do know a minimum size and it requires the same kind of start. Am I starting to get it?