You can remove members from an option policy. You replace the add: attribute with the remove: attribute and then list the members as shown in the following example:
dn: cn=has-policy,cn=options,cn=policy1, cn=tdatrootP,dc=domain1,dc=com changetype: modify remove: member member: cn=behind-the-firewall,cn=internal-network-groups,cn=policy1, cn=tdatrootP,dc=domain1,dc=com