Thanks Kevin, this is a little bit simpler.
I am testing the job at the moment to see how it works out.
Below is my SQL in the job step
IF @@rowcount > 0
BEGIN
EXEC ReportServer.dbo.AddEvent @EventType='TimedSubscription', @EventData= '73a492d4-a44c-48ec-b13f-781c6d61e313' -- subscriptionID
END