Hi Jerry,
SAP PM you can do Plant specific settings and configurations. E.g. Order types can be created for specific plants.
Coming to topic of Notifications, You can create notification types which valid across a client. Dates, Priority these things are defined at notification type level only. At plant specific level, you can configure other CMD objects such as planner group, locations, work centers.
Please let me know if you have further questions.
Regards,
Amol