Thanks, very helpful. The plan was to use the IMCR test as the flight with an instructor, which is what I've done before. Instead, I did a type conversion onto the club's new Firefly (which was useful, as I'd got very lazy about practising PFLs and was rightly brought up short by the instructor who made me do several).
So I will do the revalidation of the SEP using SRG1119E, and arrange the IMCR test when the aircraft have been fixed (annoyingly the club's two nicely instrumented aircraft are both u/s at the same time though A and C is working on both...)
Just to check - I am right that letting the IMCR lapse only means I can't use the IMCR privileges until I've taken the test? (Assuming the lapse is only a week or two.) No retraining required?