Morning Peter, Just had this situation with a student of mine, who found renewing JAR IR expensive every year, he had a multi so about £1500.00 a throw. He does not have his own aircraft. Also has an FAA IR which of course is self renewing according to approaches etc:
Answer was this from CAA:
Up to 5 years IRE can renew.
Over 5 years CAA Staff test again.
Over 7 years CAA Staff test again + retake all the exams.
He like me is hoping for the IMC to transfer to an EASA licence, at some stage, as all this becomes expensive.
And if you do no need airways, or do long distances IMC usually does the job.