In general when two standards both apply and one of them requires fewer but allows more and the other requires more it is a no-brainer that the more restrictive standard governs.
If there is an actual conflict between the two standards, where there is no solution that meets both at the same time, you have a problem that requires rewriting one or both standards.
When the same organization issues both standards, they do their best to avoid any such conflicts during the writing process.
