D365 Finance/Finance Premium mix&match for purchasing minimum?

Hi, can someone confirm if it's obligatory to meet the purchasing minimum requirements for both Finance and Finance Premium, i.e. if we purchase 20 regular Finance licenses, can we purchase only 5 Finance Premium or does it have to be the minimum 10? I've found resources online that say these 2 SKUs can be mixed & matched, but I can't seem to find definitive confirmation of this in the D365 Licensing Guide or any of MSFT resources.

Thanks!