Last week I booked the family return connecting flights to LGW.

From MMB > Seats, when I select myself + infant, all of the available D/E/F seats vanish, so I'm effectively restricted to selecting A/B/C seats. The same situation exists with the inbound flight. My other half and daughter are able to select D/E/F seats without any problems.

I queried this with the Executive Club and was advised that Infant seat selection is restricted to A/B/C on the 734 due to the location of dual oxygen masks.

I would be grateful if anyone could advise me if this correct or if I have been misinformed, and if so the best way to get it resolved.