I have ALWAYS been able to book PIT/LGA via DTW - - until a few days ago.

Around Wednesday, when I was looking at PIT/NYC in the morning, DTW connections were pricing low, like they always have. Later that evening, I noticed that nonstops were around $60, but ANY connections started at $431! Yikes! When I check ExpertFlyer, I see that all travel must now be non-stop (or direct).

I see another post today where someone says that they normally fly PHL/CHI via ATL, but, now ExpertFlyer doesn't list ATL as a valid connecting city.

Is it possible that someone has recently revamped valid fare routings?

Your thoughts.

edited to add . . . . I expect a few posts saying how DL can't make any money selling 2 seats for $60 including tax - or, I'm a gamer, trying to game the MQM system. That's not what this is about, so I'm thanking you in advance for saving your snarky remarks!