Forgive me If I'm going mad!

Last week I picked out 3 flights for my wife as she is looking to travel to Argentina. We've always used BA's direct overnight flight.

Just now, on searching their website, there are no longer any direct flights for those dates ( all between 18/7 and 1/8 ).

Have BA suddenly changed the flights or am I misreading the information? The latter would not be the first time!

The odd thing was that the return leg was a direct flight. Somebody can probably explain what's going on to me. Thanks in advance.