For the date I would like to book, there is only 1 award (Avios) seat available in Business MAD-GRU.
However, if I add a connection, e.g. LON-MAD-GRU or even a Spanish domestic like PMI-MAD-GRU suddenly there are 5 seats available...
Is this a bug in the web booking engine or do they load different (better?) Avios availability for through connections?
I've seen this before for revenue booking classes but never award seats.
I've always assumed married segments can exist in all booking classes. Last year I couldn't get LHR-MEL on QF F when I wanted it, but LUX-LHR-MEL on the same date was fine.