Let me downsize (but not completely rescind) the gripe I posted about five messages back. During last night's irritation, after fighting my way through the web-access Insider page I expected to see the Insider option on the Phone Update screen. The next time I went there, I first saw that the phone on its own initiative had searched for and started downloading the AU. I thought that meant I had successfully enabled Release Preview status, and I let the phone do its thing. After 20-30 minutes of bars and gears, it came back up and I saw to my astonishment that I had received the .189 release instead of the .187 I had expected. And there was still no Insider link on my Phone Update page.
So this morning I check for updates out of habit and -- surprise! -- the Insider link is now available. I guess I was just caught up in Microsoft's sometimes sluggish validation process for the hours I thought nothing was happening.
Now I am wondering if I got the AU last night because it has finally been released to the x3 universe, not because I managed to call for it as an Insider. Probably doesn't matter, since I am mow close to where I wanted to be at the end of the update process. I may go fast ring on this phone a few days from now, but I'm happy to have it working on a formal release while I get to know its capabilities.