[BUG] NPC builder ship never goes to new plot [v2.50]

[badbane]

Created a Plot in Heretic's End, Built a station blueprint and hired and ARG builder. The builder never showed up. I can't easily locate the builder to see what it was doing. But all of the arg builders appear to be just hunting for building missions. Did Seta for a few hours and still nothing. Reloading the game does not resolve the issue. I can't cancel or change the builder to resolve the issue.