Hi JJ, sorry but I am not much help on the specific requirements that you will have to meet, only
Lasors, CAA or wiser members of Pprune can answer those for you.
We have recently seen a few very experienced airline guys join us (though they did have previous helicopter experience.) It is recognised that they bring with them a huge amount of ‘modern’ procedural flying knowledge and experience that we are keen to tap into.
Can you give us a clue as to what part of the UK you are in?
Cheers
TeeS