Don't quote me on this. Don't quote me on this.
My best guess, from reading some of the online information, is that Boss is waiting for their field testing device to be approved by the feds. Once approved, then it is available to law enforcement, so the shot can be used. It sounds like Epic Shotshells is playing the same waiting game. The government shutdown is adding to the delays. The feds have the Boss device in their hands, but I believe they can't proceed during the shutdown.
My best guess is we are counting on conservation officers to be understanding if they check us with copper shot before that device is available. If they are the Barney Fife type, could be ugly. If they are thoughtful and understand bismuth is pretty much gone and steel sucks and tungsten isn't cost effective for most people, and we are trying to do the right thing by shooting copper, which is more expensive than steel, then not any ugly situation.
My best guess is the Epic Shotshells guy is counting on clear hulls to somehow work with an officer using regular UV lights to see the corrosion inhibiting powder glow (corrosion inhibited pure copper is what we are talking about here, and what was approved in the past, but nobody brought a testing device to market, nor the shells to market). I don't know why an opaque shell, cut open, and examined with the same uv light, wouldn't be equivalent. Maybe there has been some temporary agreement that Epic Shotshells has with the government for that combo, where they'll just eyeball the copper through the shell and let you go about your business? I don't know.
Best guess is to wait until the testing devices have been approved before using copper on animals, if you want to be 100% in the clear with the law.
Did I mention not to quote me on any of this?