I suggest having a chat with someone who deals with this kind of thing, such as
On Track aviation. As well as being able to provide you with advice on how to get the ball rolling, they also run a 1-day course which will prepare you for the interview with the CAA to give you the best chance of getting through it.
(I'm not connected with On Track in any way except as a satisfied customer.... I did my FIC course with them.)
FFF
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