You're either being intentionally asinine or just don't get the point. The trade routes should not be persisting once the planet is captured. One of the benefits of capturing an enemy planet is to shut down the trade route. In any event, I've tried that approach as a work around and I'm not sure the routes can be shut down in that manner. If you don't have something constructive to say, then don't waste time posting.

That's a good question. I don't know that I've actually been able to shut one down since the general release. I was able to do so during Beta testing so something seems to have changed. Perhaps what I noticed with the persisting trade routes is only one aspect of this more general problem with AI trade routes.

The Korx have a tech called "Fortified Freighters". Once they research this, they can build a super-project called "Freighter Command", which makes all trade routes persitant. This is probably what you are seeing.

Respectfully, I disagree with an attribution of the problem I'm observing to "as intended" game play of some kind. I'll give an example of that to which what I'm referring. The Iconians and I were at war. I conquered one of their planets from which a trade route to a distant alien planet originated. The Iconian trade route persisted even after I conquered the planet. The tiny freighters originating out of the planet were labled "Iconian." I could kill the tiny freighter and the very next turn a new one would originate from the planet. I've noticed that in several games of TA I've played since the release. Never noticed it in the Beta. That should not be happening as far as I know, even if the Iconians have the Freighter Command achievment, which was not the case in those games.

I turned in a saved game a couple of days ago. Haven't checked email to see if there's a response yet.