Transferring the AD roles are easy using PowerShell. One important issue needs to met in order to be able to transfer the “SchemaMaster” role. The admin who is performing the “SchemaMaster” role transfer needs to be in the “Schema Admins” group. Being in the “Enterprise Admins” and “Domain Admins” groups are not enough.
Move-ADDirectoryServerOperationMasterRole -Identity “dc2” –OperationMasterRole DomainNamingMaster,PDCEmulator,RIDMaster,SchemaMaster,InfrastructureMaster
Earlier post on Active Directory FSMO roles: