One of the changes that is coming into force with EASA is that a renewal must be conducted at an ATO who must make an assessment and conduct training before you take the Renewal test.
The 5 year requirement to complete that test with a CAA FE is a hangover from the old UK National IR requirements. It has never been a JAA requirement and there is no such EASA requirement. The JAA brought in the 7 year rule which is more stringent:
FCL.625 IR — Validity, revalidation and renewal
(a) Validity. An IR shall be valid for 1 year.
(b) Revalidation.
(1) An IR shall be revalidated within the 3 months immediately preceding the expiry date of the rating.
(2) Applicants who fail to pass the relevant section of an IR proficiency check before the expiry date of the IR shall not exercise the IR privileges until they have passed the proficiency check.EN L 311/32 Official Journal of the European Union 25.11.2011
(c) Renewal. If an IR has expired, in order to renew their privileges applicants shall:
(1) go through refresher training at an ATO to reach the level of proficiency needed to pass the instrument element of the skill test in accordance with Appendix 9 to this Part; and
(2) complete a proficiency check in accordance with Appendix 9 to this Part, in the relevant aircraft category.
(d) If the IR has not been revalidated or renewed within the preceding 7 years, the holder will be required to pass again the IR theoretical knowledge examination and skill test.