Is it still the case that row 1 is blocked for BAEC Gold (or above ...) until T-72? If that is the case then the only "available" pair at the time the poster took this screenshot seems to have been 2DF - but perhaps on this config, where this is also a "bulkhead" row, that is also subject to the same T-72 limitation? Otherwise SKT-DT's answer of BA IT covers every other possibility

Deleted as I was misreading the seating chart (somehow thinking that "X" were the only seats not yet taken, rather than the other way around - clearly it has been too long since I last took a BA flight ...)