...learnt that one has to either go through the FTO's pre-selection or take the Guild fo Air Pilots and Air Navigators Pilot Aptitude Assessment test as an alternative
I wouldn't say one
has to go through one of these. I certainly haven't, and I don't think it's required for most modular courses. Of course if you've never done any flying before, it's a good indication of your ability, so it could prevent you wasting thousands of hard-earnt pounds. But it's possible to get an ATPL(f) without doing these tests.
Good luck, anyway!
FFF
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