FWIW I agree with 757_Driver,
BA sets the experience levels they are looking for and if you meet them, great. I can't believe that they set a minimum level of flying experience in the ad but secretly require an extra 500 or 1000 hrs when they review the applications. That would be a waste of everyones time.
I believe that the four essay type questions are key. Really think about your answers to these, check your grammer and spelling. Do a bit of research and show that you have really thought about your answer and not just knocked it off in 20 minutes.
Regards