I've had some time to go back and consult references. 9 is indeed correct, and I am not exactly sure how we got 8 as you need an odd number, 7 would have been more understandable!
So for this CRL, I have updated the text to 9. For the other R1 based CRLs I will need to make a request to the LMO so will probably only go live as part of the new CRL system.