The UK CAA has adopted a derogation such that where a pilot holds or has held an Instrument Rating issued by a third country and that rating is compliant with Annex I to the Convention on International Civil Aviation, the applicability of FCL.625 IR(c) and (d) may be based on the validity dates of the Instrument Rating of that other country.
CAP 804, Section 4, Part G, Subpart 1, page 4/5.
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