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There are two "Dreamliners" in use by AA, with different Business seats: the Boeing 787-8 with Zodiac
angled seats - some forward facing, some aft facing (
link), and the Boeing 787-9 with
angled forward facing B/E Super Diamond (
link).
These
could have different requirements. The angled seats
probably do not allow use of approved infant safety seats because they are angled and do not face fully forward.