The only thing that would make sense would be 14th October, since the 24th September would be only for 30-something hours, lika a "flash-sale".
Anyway, that and the 50off would make me silver with a single business class return flight, gold with 3 (coming from blue...!).
I think I'll wait a little bit until all the good prices disappear (shouldn't take too long now) so that I'll have a good excuse not to book 😜.