So, I just figured out what happened with these blocks. The ones on the right side of the terminal strips were mirrored instead of being flipped. I don't know if it was me who did it, but I don't think I would've predicted this behavior.
To fix them, I mirrored them back, did a redefine, then went back and flipped them all and everything is ok.
I wonder if there's a way to prevent a block from being mirrored...