Definitely used to be 40 TPs, with other IB Domestic being (e.g. MAD-BCN Shuttle) being 20TPs, so this may just be realigning and aiming to encourage people to use the direct LON-LPA flights rather than cheaper fares via MAD.
It is a shame that BA don't have a way of updating us of changes, surely a line or two in the BAEC spamogras would mean I might read the damn things.