Four months before your revalidation date, you will receive a formal revalidation notice from the GMC.  

Your Responsible Officer can make their recommendation to the GMC at any time in that four-month period.

The revalidation notice does not usually require any action on your part. If you have had an ARCP within the last 15 months and supplied a fully completed and up to date Form R, your RO will use this as the basis of their revalidation recommendation. 

If further information is required, you will be contacted and asked to provide this.