TPs earned on the 8th will credit the old year, sadly – barring a case of BA's IT feeling poorly and you needing to claim the TPs manually. The interaction with the triple Avios offer is anyone's guess.

If you would otherwise have been minded to use BOB for some refreshments, need to be off the plane promptly, or like the prospect of not sitting next to anybody, these would tend to militate in favour of buying.