[BUG] Disappearing Caravans

As a Kingdom, after I researched the Trading tech I built three caravans at three different cities.  After they were all built I sent them out to establish a trade route.  Before they reached the city to establish the route, I saved the game and quit out.  When I loaded it back up, all of the caravans were gone, but the game thought I had built them because it wouldn't let me recruit any more (Trading limit).

Unfortunately I don't have a before and after save file because I was actually having fun and no crashes, so I kept on playing.