The CAA has published a document http://www.caa.co.uk/docs/33/InformationNotice2015009.pdf which changes slightly the IMC renewal form SRG 1176.
The new form requires that it be copied to the CAA because they want to monitor the number of current and renewed IMC ratings. The purpose is to develop a database in readiness for an approach to EASA in 2017 for the continuation and value of this rating. (Permission for the continuation of the IMCr presently only goes to April 2018).
The CAA will be able to monitor incidents involving IFR for pilots with the IMC rating. At present the only information that CAA have are new IMC ratings issued in a particular year.