If after calling BAEC to verify that they don't see redemption possibilities (it's just a once a week flight, on Saturdays, for much of the year), you can always strategize how to take advantage of LATAM redemption possibilities (i.e. open a LATAM account and transfer credit card points to it, or ask one of your friends with excess LATAM points to come to the rescue....). If you have any AAdvantage miles, it would certainly be worth giving them a call.

[fwiw, I've sometimes had much better luck using AAdvantage miles than BAEC Avios in booking LATAM domestic redemptions. AA doesn't have LATAM flights available online, and somehow the process used by some AA telephone CS agents sometimes results in many more available flight choices than what I see on britishairways.com. Intra-Chile flights cost 6,000 Aadvantage miles one-way in the rear cabin....a very good use of a small pile of excess or "orphan" AAdvantage miles.]