Thank you for the answers guys.
I will message tomorrow the UK CAA and figure out what they need for me to comply with the exception and be able to self certify.
@Lepo: you wrote about the Bristol Atpl + Database question bank.
That should be around 2,500 $ right? Somebody else was suggesting me to go on websites like aviationexam.com and use their database (it should be updated regularly and it includes more than 14k questions)
Any particular reason on why should I not go with that method (way cheaper than Bristol?)
And also, you all pointed out that the ATPL is valid for 7 years after the expiration of my IR: does that mean from the date I get my skill test and I convert ATP into Atpl? And how long do I have between the completion of the ATPL theory and the skill test?(not sure if the 36 months that paco was writing about is that term).
@paco: do you happen to have some kind of reference on the fact that the 1,500 hrs have to be PIC by chance?
I appreciate all the help you are giving me!