Join Date: Aug 2011
Location: Barcelona, London, on a plane
Programs: IB+ Gold, TK E+, Hyatt Globalist, Marriott LTP, IHG Diamond
Posts: 14,191
What gives you the impression that IB-booked awards give you a checked bag on LATAM domestic whilst BA doesn't?
I can certainly confirm that my recent IB+ award flights on LATAM (TATL and Argentina-Brazil) had a checked bag allowance. Not sure about Brazil domestic, though.
But given all of the very good reasons to prefer booking awards via BA, what makes you so sure that BA awards wouldn't book into the same "Plus" fare category?