Previously, previously, previously.
I love these inside looks at the new club construction.
So they were dropping into wet concrete? That stayed wet from dawn to dusk?
Google concrete admixtures. Adding a retardant to concrete, like sugar, will slow the setting process. Add enough sugar and the concrete will never set, so it must be possible to make a mix that stays liquid for 12 or 24 hours.
I've heard that many building sites keep a tank of molasses on site for this (presumably for accidental spills, rather than sudden desire to create art instead of buildings).
Why not drop first and add concrete when they're done?
I don't care about new clubs or concrete admixtures or why not drop first and than pour concrete - this is electrifingly beautiful.