The highlighted (i.e., in red box) comment, on the last line above, sums it all up — the impression that Garmin released it before it was ready to be released.
That was what they did with the Vivoactive 3 — as I found to my cost.
I had a hunch this would happen with the Forerunner 645, which is why I have maintained, from the start, that I was going to wait. I am so glad that I did NOT rush to get one.
I am, as you can see, monitoring this and keeping you posted. I will continue to do that.
It is, however, possible that I might not get a FR 645 after all! I might get a Forerunner 935 instead. It is a proven product which appears to be solid, stable and reliable.