Part FCL Appendix 9 Para 16
I think this is for "
SPECIFIC REQUIREMENTS FOR THE SKILL TEST/PROFICIENCY CHECK FOR MULTI-PILOT AIRCRAFT TYPE RATINGS, FOR SINGLE-PILOT AEROPLANE TYPE RATINGS, WHEN OPERATED IN MULTI-PILOT OPERATIONS, FOR MPL AND ATPL".
But anyway... having read all the Apendix 9 a couple of times I guess there is no limit or minimum for the flight. I think it can be done in one single flight as long all the mandatory (M) items are completed. And have to do section 6 a 3b because of the MEP and IR renewal.
Will let here the result when I know it for sure.