Correct, except it is RENEWAL of the SEP class rating not REVALIDATION. See FCL.740 for renewal requirements (or CAP 804 Section 4, Part H, Subpart 1, page 6 where this is reproduced):
(b) Renewal. If a class or type rating has expired, the applicant shall:
(1) take refresher training at an ATO, when necessary to reach the level of proficiency necessary to safely operate the relevant class or type of aeroplane; and
(2) pass a proficiency check in accordance with Appendix 9 to Part-FCL.
See also FCL.010 Definitions for definition of Revalidation and Renewal.
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