I don't think they'll whittle down section by section - they'll take the scores from all tests, interviews, CV, weight them, and then take the top however many then need.
They'll be a few that they can reject straightaway, that either don't meet the criteria, or from their interview they knew in the first few minutes that they're not suitable.
I've done a lot of recruitment in different industries and that's the typical process.
Or who knows, TUI may have done as you say.
Either way, not long to go and whoever gets through to the assessment day, please ask the question (for the sake of curiosity of course!)