It's a bug. I'm guessing I've messed up the ship spawning code and it mangles deploying it to the next chunk of map.
I'd like to fix it, but I've had 6 new ideas for blocks (tractor beam, slaver drill, support fighters, etc.), an idea for an open map with long range sensors, and some thoughts on a lunch break length campaign across hostile space.
After I've updated my previous game release I'll be able to risk going near the code.