I know Bruichladdich has said they do this for the Laddie Classic (a bottling I really love). Source: just trust me bro. I don’t recall when or where I heard that. Possibly they do it with other bottlings, and surely other distilleries are doing the same thing. Bruichladdich didn’t invent the process. But it’s not a well studied, documented, or promoted element of whisky ageing, because, I think, it’s not as sexy as infusion and evaporation. Among other reasons. If you’re curious, I could spin a yarn.

Any distillery that chooses to do this, certainly does it for a reason. Disgorging and re-casking a batch is a massive pain in the ass, and holds up warehouse space & production timelines - two things a bean counter with no sensitivities to flavour would be happy to cut out.