Scheduled notifications possible? API? Scheduled test of notification rules?

We use different service groups for different notification rules. So we can can put this SMS service into desired group and notification would be exactly as for any other failed service within this group. In your example you would create a service group including NetApp stuff and the SMS thing. Works like a charm and you can be sure that correct notification rule is triggered.

For the API-stuff: sorry, I do not know a way to do so.

Regards,
Tom.