According to Standards Document 25 v3:
An IMC Rating or IR(R) is valid for 25 months. If the rating has lapsed by more than 5 years, the applicant is required to carry out dual training with an instructor before taking the renewal test. If the rating has lapsed by more than 10 years, the applicant is additionally required to pass the IMC Theoretical Knowledge Examination.
However, as the applicant held a valid ICAO IR(A) within the last 2 years, do the 5 and 10 year credits from training courses and theoretical knowledge exams apply for IR(R) renewal?
Note, however, that the FEH states:
Expired rating: If the rating has expired by more than 5 years then training at CFI’s discretion is required plus a full initial IMC Rating test. Logbook and Form SRG1125 must be sent to L&TS.