The manufacturers have a long delay in the shipping, due to the delay in the producing. There are simple not enough processing units from their suppliers, but if you want only a few machine, of course, they have stuffs in stock. For a nice premium.
Into the mining, new players have arrived, the institutions. And they make their orders with few thousands pieces, and set the mining budget in tens of millions of dollars. For example, an average 15 million dollar facility means 5000 ASICs, and that is a relatively big amount for the manufacturers.