As for the confusion regarding results and entry requirements. If NARIC confirm that you have the equivalent results then you're all set to go and submit your application. If you are unsure but you think that you have probably met the requirements, then you may as well submit your application anyway. You will still have time to contact NARIC in the meantime and your application won't cost you anything until you actually book your assessment. I assume that BA will assess your qualifications during the initial screening process and therefore if you are invited to the assessment stage then you should be quite confident that you ok to proceed.
I have a query about the assessment day at OAA. According to their website, the assessment day will consist of computer based testing, group exercises and a formal interview, all conducted in one day. Does anybody know if this is definitely the case? If so, this is different to last year whereby the assessment was split over 2 different days (first day computer based testing, and second day consisted of group exercises and interview and was conditional to passing day 1).