I think I may have tracked down at least part of the problem: a "ghost contract". In my current playthrough, I know I've only seen two rescue missions, and I've taken both. Both of those kerbalnauts (Thomkin, Bartdred) are active in my normal flight roster. But a third rescue mission for "Brian" appears in my persistent save... and I've never seen that name pop up in ANY of my playthroughs. I was surprised to see it in use at all. It's possible that a rescue mission came up, I ignored/didn't notice it, and it expired, however. In either case, the "rescued" kerbal is not showing on the roster. Adding him (as though fired) seems to have fixed things. Something for the debugging crew to chew on, perhaps.
