They don't want to even contemplate storing a warehouse full of new Z9's. They understand that moving stock is business. They want all sold long before production starts rolling them out and they have estimated a LOT of production.
Most should be "considering" whether they've had Z9's (not "mini") mining since late summer of 2017. I would be surprised if they're manufacturing more Z9's (not "mini"). They did that a LONG time ago [More than likely] FOR THEMSELVES. Why sell everyone money printing machines that they can simply use for themselves? First, they mine for themselves. THEN, once profitability has decreased -OR- threat of a fork appears imminent, begin selling hardware.