I agree with Billie Bob on this one. For a laugh, download the pdf from
the JAAsite. You want JAR-FCL 1.
Relevant pages, page 84 (JAR-FCL 1.250 (4)) and page 123. (JAR-FCL 1.285)
It would seem if you have 1500 hours in MPA's then the conversion is a bit easier. Need only do 1 composite exam but I am not sure how the UK CAA will apply the JAR MPA compliance when sitting the LST.
(I don't work for the UK CAA, I just wade through PDF's)