Yes, it is mandatory to convert your licence to the EASA due to the fact that it is expiring. CAA is not issueing JAR licence any more.
In this case you will actually have to complete CAA Form SRG 1104 for the conversion. The conversion fee is £73.
Be adviced that your SEP Rating must be valid too. If it is not, your application will be denied.
Be adviced that your FAA licence must be revalidated thereafter.
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