My Joann's told me in either January or February that they were changing suppliers for their fat quarters. I have noticed the difference too. And while they may be "correct" as advertised, it is yet one more inconsistency in a world where we increasingly ignore the tried-and-true standards. We can't count on anything when we try to plan now.
So I always buy two and only if they are half-price that day. But I'm not liking the quality of the cotton either, so I'm going away from FQs entirely.