Supplier Capacity Calendar setup

Hi All,

We would like to maintain ASL at local and not global as there are different procurement teams around the world and the procurement is done from different suppliers for the same items (as some are locally sourced). But now cannot add Supplier Capacity Calendar to the ASL as Planning Constrains Tab is greyed out when using Local ASL.

Does anyone know why this works only if the ASL is setup as Global and not when its Local. Is there any other profile option or some other setup which would enable the Planning constraints tab for attaching the supplier capacity calendar.