IThink - so it's you!!!!
That's why I can never get to 9A first on a BA A319
And just to echo what you say, on BA you can choose an emergency row at on-line check-in - you then have to check a box to say that you understand what you have done and you meet the criteria.
Mind you, there's nowhere near so much room in the emergency rows on a BA A320.
Yours folded awkwardly.
Atlantean.