Thought perhaps someone here could shed possible light.

The situation: reservation made through British on codeshare flight MAD-MIA for July of next year.

Seat selection option in BA flight management links to Iberia website. Iberia website says flight not eligible for early seat selection.

Called Iberia. Reservationist had to consult with supervisor; told airline is "making changes" to aircraft and business seat early selection won't be available "for a few months."

COULD this be because premium economy seats are being installed? What other possible/reasonable reason? Aircraft is scheduled as an A330 but who knows?

Figure I'll wait those "couple of months" and try again but am I missing something and thanks in advance.