In the current market most of the casks you can buy are coming from blenders, so the main part will be refill casks without any indication about it being 2nd, 3rd or whatever fill.
And it will be mainly ex-Bourbon casks.
The distilleries are simply not offering 1st-fill Sherry casks any longer and something special like wine casks are generally not on the market.
That’s why most of our customers have started their own cask management and re-rack.