Good citizens of Racoon City, I am be honoured, humbled, to be nominated for such a role amongst a capable group of development afficionados. My bat senses tell me that @innsertnamehere's suggestion that the first ground floor slab pour should be the determinant of reaching grade is well reasoned. Should it be necessary to actually arbitrate the date of said accomplishment, I hope to be available. Should I not be, my resourceful young assistant Robin will no doubt be eager to "call it" as you kids say. It's my uderstanding the lad is quite keen himself on seeing this erection pop up out of the ground, I believe that's what I heard him exclaim from behind his laptop one evening, something akin to "Holy megacolumn, this is The One". He's looking forward to his first Appletini, and I believe I may allow our but… I believe I may allow our colleague Mr., uh, Miller to mix him one on this occasion.
Also if they will pour the concrete before or after the next piece is attached. Should be fun to watch.