No doubt JRiver has it's reasons for how it characterizes the status of the current version versus its predecessor. Whatever those reasons are, I don't think they're likely to make any difference to established users once the "beta" is made available to everyone. At that point, an understanding of what it
is is probably not helped by any labels—official or otherwise.
It's not a new program. It's a continuation of the development of the previous version, and development of the previous version ceases. Yes, relatively significant and experimental changes are implemented in the early days of the changeover—while in
closed beta. But after a number of weeks, the issues arising from such changes are dealt with. After that, the nature of the changes is really not much different than the ongoing changes made to a version that has been declared "released."
So what does this mean? It depends on who you are. I'm inclined to switch to the new version as soon it's available. If I can't discern any difference in "stability," I see no reason to deny myself the improvements in the new version. Not wanting to waste time using two versions, I'll stop using the old version at the same time, and uninstall it soon thereafter. Others will not be as interested in current development, or simply reluctant to change something they're happy with. They might hold out until the list of improvements is too long to ignore. Or they might just wait indefinitely until JRiver announces the new version is "released."
At this point, declaring MC16 "released" is a marketing event having little to do with development. JRiver will want to pick a time they're sure the current version is
very stable, with no significant changes planned for a while. They will hope many "holdouts" will upgrade when the announcement is made, and they will want those users to be pleased with the set of new features and improvements they're getting for their (full) upgrade fee. So I don't think they'll declare it "released" in response to your request. And you've already understood the hints it's not really in beta and we should be happy with our decisions to upgrade early.