[r9etb]

When the ninth state ratified the Constitution what instantly became the status of the 4 states of the former "perpetual" union under the articles of confederation who had not yet chosen to ratify the same?

Not a dilemma at all. It would be a Union consisting of 9 states: "shall be sufficient for the Establishment of this Constitution between the States so ratifying the Same."

The status of the other 4, would be that they were not members of the Union until they ratified.

Which they did, and thereby became states. There's no "dilemma" about it.

[dangus]

I almost answered similarly, but I checked my facts first. It turns out that the Articles of Confederation remained in effect until the last state ratified the Constitution, at which point they were not rescinded, but merely moot. Since the Constitution was created under the color of law of the Articles, and since the Articles themselves prohibited their dissolution, and since the Constitution is not inconsistent with the Articles (unless you subscribe to the nonsense that the Constitution is dissoluble whereas the Articles were expressly not), one could argue that the Articles are still in effect today, as amended.

[Bigun]

The status of the other 4, would be that they were not members of the Union until they ratified.

But what had happened to the "perpetual" union they had just joined 6 years earlier?