Ships Randomly Changing Owners

Description

The present game I am in is a small quadrant with 7 players, including myself. Using Standard SEV with version 1.17, at turn 70, I was gifted with an enemy ship. Now here's the catch: Not only is my domain completely cut off from the rest of the quadrant (that's how the game started--me in three systems that were disconnected from the rest), but I have no technology that would allow me to gate to a system I have never been to.

I noticed the mysterious gift of an enemy ship when I encountered combat with player 7. I thought it was an enemy that had opened a gate, but I was wrong. Instead, they were fighting their own vessel. But apparently, it was no longer their ship. I've reloaded the saved game numerous times (between game restarts and system reboots), and most recently noticed that I already had the ship, and now after the combat, I have all three ship designs that attacked. We're still cut off, so it's odd that this should occur. To verify, I have attached the saved game. Just passing one turn should result in combat with Player 7.

I tried going back one saved game to when I didn't have the ship and progressing one turn, but unfortunately, that failed to reproduce the bug. This means that it is a hard to find bug, but it may be a contributer to the saved game errors I mentioned earlier: Whatever data structures are being used to store information are being buggered with.