I think I just caught an AI builder ship teleporting to it's destination.
Their Builder moves at a slow 2 spaces per turn, while mine moves at 6 per turn thanks to Relics and Faction Trait. Moving alongside their builder unit, my own was "racing" theirs to a destination, and at the time of the incident our builders were adjacent. Abruptly, on the next turn, their builder disappeared and a space station appeared 12 tiles ahead.
Anyone else noticed suspicious activity? Or can anyone come up with an explanation? I'd say they might have just had a builder I couldn't see, but then what happened to the other builder I was adjacent to? The space station appeared in a spot within my territory but they would have had to move through my territory to reach it, so why wasn't I warned with a message?