Uhm, my only doubt is: how in the world they moved a whole datacenter to another in just 24 hours??
If you know the job (unmount equipment from the rack, disconnect cables, move equipment, replace equipment on new racks, connect cables) you notice its' almost impossible to do that. Also if they moved entire racks, I expect the operation to endure at least 1 week of 24/24h work.
I'm confuses about that aswell. But who knows how their data center looks maybe they use containers that are placed in large buildings. Simply connect power to the containers and go!
You forget that their DC#2 was already kitted out for GPU's so all infrastructure was already in place.
So all they had to do was physically move the equipment.