See CAP804 Section 5 Part E pp4-5 para 3.5.
Your IMCr may be revalidated by flight test during the present period of validity; this test may be conducted by any Examiner who is currently empowered to do so. Whether or not he/she conducted the original test is immaterial.
An IMCr is valid for 25 months from the date of test. So if revalidated early you will in effect 'lose' some unexpired validity. I have also asked the CAA to confirm whether the IMCr revalidation flight test may be accepted in lieu of the '1 hr training flight with instructor' for SEP Class Rating revalidation by experience under FCL.740.A(b)(1)(ii) (as is currently the case).
It will probably be simpler (and perhaps cheaper) to revalidate or renew your IMCr after 17 Sep 2012, then submit your licence and rating for conversion.
Last edited by BEagle; 28th August 2012 at 07:03.