The hiring processes of airlines abroad is very different than what we are used to in the west, the first mistake is to consider that there is such a thing as a "pool" there isn't, not like we know it. When you are informed that you successfully passed the interview process only means that your application went to the next step and that you are being further evaluated with the results of the background check and they grade all the applicants that have passed up to that point and select the ones that scored the highest overall score during the application process and those get the job offer, having passed the interview doesn't mean in any way shape or form that you have the job it only means that you are on the "semifinals" of sorts, the first thing you need to do when applying for an international job is to forget your concept of things like "hiring pool" it doesn't exist. Individuals that have been sent letters saying that they no longer are being considered it is not that they got flushed from any pool or a job offer have been retracted, it simply means that you didn't make it to the finals.